Flying disc techniques

Last updated

Flying discs (including Frisbees) can be thrown in many ways. Each throw involves snapping the wrist as well as flicking the arm to impart gyroscopic stability to the disc and accelerate its mass to a certain velocity. Without spin, a disc will wobble and fall; without velocity, the disc will not go anywhere. Using these two guidelines, any number of throws are possible. Most discs are designed to create lift when thrown with the flat side up.

Contents

Techniques

Right-side up

Trajectories of tilted discs
Red: Axis of thrower's body
Blue: Outside-in curve
Green: Inside-out curve Frisbee Throw Curvature.jpg
Trajectories of tilted discs
Red: Axis of thrower's body
Blue: Outside-in curve
Green: Inside-out curve

Right-side up throws are all similar in that they react the same way to the tilt of the disc when it is released. A disc thrown right-side up will accelerate in the direction of the low end of the disc. A disc tilted leading-edge up will lose speed at the end of the throw and make a gentle landing; if tilted sideways (known in aeronautics terms as roll), it can curve around objects.

There is a language for describing throws that curve. Both descriptions are relative to the direction the person is facing and intends to throw. This axis is marked in red in the picture.

In disc golf, inside-out throws are referred to as "hyzer" throws and outside-in throws are known as "anhyzer". "Hyzer" is a reference to H. R. "Fling" Hyzer and the etymology can be traced back at least as far as 1975. [1]

Backhand

Frisbee-power-backhand-top.jpg
Backhand Grip, Top View
Frisbee-power-backhand-bottom.jpg
Backhand Grip, Bottom View

This is probably the most commonly learned throw, and also one of the most powerful.

  • Grip: Fingers are curled under the disc's rim, and the thumb is placed on top of the disc to hold it in place. The index finger may either be on the edge of the disc (to help aim), or four fingers may be tucked underneath the rim (to aid power).
  • Throw: The thrower draws the throwing arm across the body from the left to the right (for right-handed throwers) to build velocity for the disc. During this movement, the arm straightens out. As the arm becomes straight, the wrist is flicked to impart spin. For backhands, the thrower should step with his strong leg (the same side as his throwing arm) forward or across the body to allow a smooth, accurate throw.
Variations
  • The High Release: Used to get around an object (or a person), the High Release is thrown above the thrower's shoulder, and relies more heavily on the flick of the wrist to impart power.
  • The Air Bounce: This throw is released at a downward angle, but with a high angle of attack. This throw will move toward the ground at first before downwash causes it to rise, giving the visual effect of the disc "bouncing" in the air. This is done by pressing down with the thumb, which lowers the trailing edge at the instant of release.
  • The Beach Backhand: Rather than reaching and throwing the disc across the body, the arm is curled and the disc is cocked next to the hip on the same side of the body as the throwing arm. The disc is released by extending the arm straight ahead and snapping the wrist. The term "beach backhand", or "barbecue backhand" as it is sometimes called, is considered pejorative, as this release technique is inferior to a standard backhand. It is also sometimes referred to as the "chicken wing" as it involves an awkward cocking of the elbow, mimicking a chicken wing.
  • The Shocker: Stepping outside with the non-pivot foot (as if preparing a low-release forehand throw), hold the disc with a backhand grip to release the disc very close to the ground and between the thrower's legs. Even if it has only limited range, its uncommon release point makes it very difficult to intercept since the disc is bound to fly between the legs of the mark (if they have stepped out to try to intercept a low release forehand throw.)

Forehand (sidearm)

Frisbee-forehand-top.jpg
Forehand Grip, Top View
Frisbee-forehand-bottom.jpg
Forehand Grip, Bottom View

This throw is also known as the flick,two-finger, or the side-arm. Focused in the wrist, this throw takes little time to execute. Along with the backhand, it is one of the two most common throws used in Ultimate, as it allows throws from the opposite side of the body from the backhand. [2]

  • Grip: The middle finger is extended and laid along the rim of the disc. The index finger is placed against the middle finger for power, or pressed on the bottom of the disc pointing towards the center for stability. The thumb is pressed against the top of the disc. The wrist is cocked back, and the arm is extended out from the body.
  • Throw: A snap of the wrist imparts spin as the disc releases off the middle finger, as well as some forward velocity. Extension of the lower arm provides additional power, as does shoulder and upper body rotation, although too much reliance on arm movement can lead to "floaty" throws with little spin.
Variations

The forehand is a versatile throw, and can be adapted to many different situations.

  • Different wrist or arm angles on release can allow for inside-out or outside-in curves.
  • Most upside-down throws (see below) use the forehand grip and use the same wrist snap and release, and are therefore variants of the forehand in some sense.
  • The High Release: Used to get around an object (or a person), the High Release is thrown above the thrower's shoulder, and is powered by the flick of the wrist as well as the rising action of the arm on release.
  • The Pizza Flip: Used primarily in faking, the Pizza Flip is executed by starting a standard forehand throw; but at the last moment rotating the disc counter-clockwise (for right handed players), under the throwing arm, using only the middle finger and the momentum of the spin to hold the disc. The Pizza Flip is then released towards the dominant side of the thrower, perpendicular to the direction of the standard forehand throw.

Push Pass

Frisbee-push-top.jpg
Push Pass Grip, Top View
Frisbee-push-bottom.jpg
Push Pass Grip, Bottom View

A relatively little-used throw, it is thrown with a grip similar to a backhand (index finger on the outer rim of the disc, thumb on top, other fingers curled underneath) but is released on the forehand side from a forehand stance. A pronating wrist snap similar to a forehand release pushes the disc forward, while spin is imparted "backwards" (i.e. spin will be in the same direction as when thrown backhand with the same hand) by rolling the disc off the index finger. A final flick of the index finger finishes the release. It is difficult to impart as much spin to the push pass as one can typically impart to a forehand or backhand, resulting in a less stable throw. It is useful in Ultimate for very short throws released to the forehand side.

Thumber Forehand

Frisbee-beach-top.jpg
Beach Grip, Top View
Frisbee-beach-bottom.jpg
Beach Grip, Bottom View

Is also known as The Beach Thumber, Peach, or in the sport of guts, simply as a thumber. Its primary advantage is that it can be thrown quite hard and with a great amount of spin, and is relatively easy to learn. It is often seen used in a game of Guts due to its power and velocity. It is unpopular in Ultimate due to several disadvantages when compared to the standard forehand. It is relatively difficult to impart different curves or release angles to, it is harder to release extended away from the thrower's body, and it makes for slow grip transitions to a backhand or hammer.

  • Grip: The thumber derives its name from the grip: it is thrown on the forehand side with the thumb under the rim and the rest of the hand against the outside of the disc. The arm should also be tucked against the side, and the elbow bent. The disc is kept parallel to the ground and the wrist is cocked back.
  • Throw: To release, the wrist is snapped forward. Spin is imparted off the flat part of the thumb; power can be gained by rotating the arm at the shoulder or the body at the hips. A flat release is critical to a successful thumber forehand.

Finn

An extreme version of the high release backhand whereby the disc is released at a very high point. It differs from the regular high release in that there is less emphasis placed on spin and the release point is situated above the thrower's head. The lack of spin ensures the disc drops fast making it a favoured quick placement throw for dump passes. Good throwers can send the Finn long distances making it a favourite deep throw against straight up marks and zones often replacing the hammer due to the stability associated with the disc movement.

  • Grip: The Finn is gripped in a regular backhand fashion with slight variations. The index finger is loosely positioned along the outside rim and the three remaining fingers are pointed towards the centre on the underside of the disc as opposed to gripping the inside rim. This ensures that the disc remains parallel to the ground even at great heights.
  • Throw The majority of momentum is built up from the vertical motion of the throwing arm. When the arm is almost fully extended vertically, a slight circular motion imparts forward velocity. The disc should be released in between the index and middle finger. The amount of spin created by snapping the wrist dictates the length of time it remains floating in the air and should be altered according to the situation.

Overhand

Also known as an "overarm" or "chicken wing." It was a primary throw during the early days of Ultimate, when it was still played using Wham-O Masters discs, because it allowed for a release from the forehand side, and flight stability of forehands was problematic with that model. With modern equipment, the forehand release is generally preferred, for multiple reasons: it allows greater sideways arm extension (useful in moving the disc around defenders), has a shorter and quicker wind-up, and enables greater control and variation of flight paths. The Overhand is now most useful when the disc is caught above the head and must be thrown quickly without changing grip. It is similar to the Hammer in that release typically (but not always) occurs above shoulder level, but comes with a different set of drawbacks. This throw is often used in attempts at The Greatest.

Grip: The fingers of the hand are spread out over the top, with the thumb under the disc and perpendicular to the rim. For greater control, extend the index finger along the rim, as in the control grip for the forehand.

Throw: Hold your arm horizontal and behind you, then quickly bring it forward, snapping the wrist laterally as you release. Typically, release occurs at or above shoulder height, although it is possible to release at waist height or lower. The whole body and arm can be allowed to rotate, and the forearm must move very quickly to impart enough momentum to send the disc a significant distance. For maximum power, the entire body rotates, as in the ancient discus throw seen in track and field events; for a right-hander, the torso starts leaning right, and ends leaning left. Wrist snap is especially important, as the throw has no stability without a strong spin.

Duck

Also known as a bear claw, a duder, a biscuit, a bow tie, or a useless. It is thrown with a similar grip to the Overhand, except it is the backward version of it. While the Overhand is thrown with counter-clockwise spin (for right-handers), the duck is thrown with clockwise spin. It is usually thrown with the arm out to the side or above the head. It is called the duck due to the shape of the gripping hand during the throw, as if making a duck shadow puppet. This throw is used in attempts at The Greatest (jumping out of bounds and throwing the disc back into play while in the air).

Upside-down

A disc thrown upside-down has a very different flight path than one thrown right-side up. The lift force does not enforce stable flight as it does on a right-side up disc, resulting in a more of a parabolic arc in flight. As with a right-side up throw, however, the flight path of the disc will curve toward the lower edge. This banking effect is most pronounced when the disc is at a 45-degree angle, and less pronounced when it is near-vertical, or near-horizontal.

Gyroscopic precession causes the disc to rotate toward horizontal through its flight path. Unlike a right-side up throw, however, an upside-down disc will not precess toward a stable flat state, and will instead oscillate past horizontal and begin to bank in the opposite direction. This shuttlecock-like effect is known as "helixing", and is generally avoided due to the difficulty in controlling a helixing flight path. For this reason, an upside down throw is typically released with either clockwise rotation and the left edge up, or counterclockwise rotation and the right edge up. The longer the disc is expected to remain in the air, the closer to vertical it must be at release to avoid the helixing effect.

Hammer

Throwing hammer Ultimate frisbee, Tartu 2013-01-20.JPG
Throwing hammer

Is gripped just like a normal forehand throw, and is generally a mid-range, high and arching throw.

  • Grip: Identical to the forehand.
  • Throw: From an open stance, the throwing arm is swung over the head in a similar motion to an overhand throw or volleyball spike. The disc is released using a wrist snap identical to that of a forehand. The angle of the disc on release can be anywhere between vertical and nearly upside-down, depending on the flight path desired.

A hammer, when thrown by a right-handed thrower, will arc up and to the left as it moves away from the thrower, and will bank towards the right in flight. The banking effect will be more pronounced if the disc is thrown higher and spends more flight time near a 45-degree angle. There is a variation of the hammer called the "Horseshoe" where the thrower takes a step towards his dominant side and throws the disc over and somewhat behind his head. This is used primarily for fake-outs in short to mid-range end zone passes, and it is effective because it appears to go the opposite way that the defender expects. One may think of this throw as the hammer equivalent of a behind-the-back throw.

Scoober

Another upside-down variant of the forehand, the scoober (also known as the spoon pass or hiawatha) is similar to a hammer, but released away from the body from a backhand stance, instead of over the head from a forehand stance. The scoober travels in a path similar to the hammer, although the initial release is typically more flat than a hammer release. Although it is more difficult to impart power to a scoober than a hammer, a scoober can be an effective short-range (10 to 20 yards/meters) throw and is used in Ultimate for breaking the mark and to throw over defenders in a zone defense.

  • Grip: Identical to a forehand or hammer.
  • Throw: The thrower steps towards the backhand side, holding the disc upside down and bringing the throwing arm across the body. Leading with the elbow, the throwing arm is swung forward, and the disc is flicked off the middle finger (as in a forehand), releasing the disc upside down.

Thumber

Frisbee-thumber-top.jpg
Thumber Grip, Top View
Frisbee-thumber-bottom.jpg
Thumber Grip, Bottom View

The thumber (not to be confused with the thumber forehand ) is a throw that is rarely used in competitive play, compared to the Hammer or standard forehand. It has a flight path that is the mirror-image of the Hammer (arcing high and to the right for a right-handed thrower). It can be useful when the disc needs to drop quickly and fly with an opposite curve to a Hammer in order to avoid defenders. In disc golf, this throw is also referred to as the "hook thumb"

  • Grip: The thumber derives its name from the grip: the disc is held with the thumb tightly against the rim and the rest of the hand against the outside of the disc. The wrist is cocked back in a similar fashion to a forehand.
  • Throw: Cock the arm backwards, then bring it forward in a similar motion to a baseball pitch. The disc is released by a forward wrist snap.

Wheel

The wheel (also known as the wheel of death) is similar to a hammer or thumber but thrown with a backhand grip. The flight path is similar to the hammer but starts out more vertical and tends to drop faster.

  • Grip: Identical to a backhand.
  • Throw: The throw begins with the hand cocked just above the shoulder, rotated so that the disc is near vertical with the upper side of the disc facing the thrower's head. The arm is straightened in front of the thrower with a backhand wrist snap to release.


Rainbow

The rainbow (also known as "Matador") is started from a standard backhand stance, but with a wide, straight-arm movement so that the release point is directly above the head of the thrower (the name comes from the wide, straight arm movement that follows a wide arch). The disc is released almost perpendicularly to the ground, and flies like an off-hand hammer (hence, like a lefty hammer for a right-handed throw) It differs from a Wheel as it starts from a backhand position (hence, sideways, instead of forward-facing), and it is released with a straight arm and wrist, while the Wheel requires bending both. It can be see as the backhand equivalent of a hammer, while the wheel would be the backhand equivalent of a scoober.[ dubious ]

  • Grip: Identical to a backhand.
  • Throw: The throw begins with a standard backhand stance, but instead of rotating the arm in a wide horizontal arch it is rotated perpendicularly to the ground, for a release point above the thrower's head. The wrist may be slightly bent to change the plane of rotation of the disc at the release point.

Blade

The blade is a throw that can neither be classified as right-side up or up-side down, because instead of the flat plane of the disc being relatively parallel to the ground, it is instead relatively perpendicular to the ground. With this throw the disc cuts through the air like a blade and does not float or have the same lift that most other throws do.

Table of basic disc throws

SIDETHROWPATHSPINHAND
SideNameAcronymNaturalHyzerAnhyzerSpinHand
Rightside-upBackhandBHR

L

L

R

R

L

-1

+1

RH

LH

ForehandFHL

R

R

L

L

R

+1

-1

RH

LH

Push PassPP0

0

-1

+1

RH

LH

Thumber ForehandTFHL

R

R

L

L

R

+1

-1

RH

LH

OverhandOHR

L

L

R

R

L

-1

+1

RH

LH

Not side definedBladeBL

R

+1

-1

RH

LH

Upside-downHammerHR

L

+1

-1

RH

LH

ScooberSR

L

+1

-1

RH

LH

ThumberTL

R

-1

+1

RH

LH

WheelWR

L

+1

-1

RH

LH

This table represents the fundamental disc throws with classic technique in the forward form, in fact exist many variations of throws and grips that make the number of pitches quite infinite.

The natural path is the trajectory the disc takes without pre-release tilt.

The hyzer path is the trajectory the disc takes when the outside edge of the disc is tilted downward.

The anhyzer path is the trajectory the disc takes when the outside edge of the disc is tilted upward.

The spin is the rotation of the disc.

Every throw can be done with the right hand or the left hand and this is shown in the hand column.

RH=right hand, LH=left hand, R=the path tends to the right of the thrower, L=the path tends to the left of the thrower, 0 means that the path is quite linear.

So R with RH and L with LH are outside-in (OI) paths; R with LH and L with RH are inside-out (IO) paths.

In spin column numbers represent the sign of the angular momentum relative to the upside of the disc (+1=positive (counter-clockwise rotation), -1=negative (clockwise rotation)).

Throws may be signed as follows: hand acronym+throw acronym+tilt acronym. For example LHBHIO is an inside out backhand throw pitched with the left hand; RHFH0 is a linear forehand throw pitched with the right hand. To have linear paths the disc must be released with a light opposite tilt than his natural path.

See also

Related Research Articles

Badminton Racquet sport

Badminton is a racquet sport played using racquets to hit a shuttlecock across a net. Although it may be played with larger teams, the most common forms of the game are "singles" and "doubles". Badminton is often played as a casual outdoor activity in a yard or on a beach; formal games are played on a rectangular indoor court. Points are scored by striking the shuttlecock with the racquet and landing it within the opposing side's half of the court.

Disc golf Sport in which players attempt to throw a disc into a target in the fewest throws possible

Disc golf is a flying disc sport in which players throw a disc at a target; it is played using rules similar to golf. It is usually played on a course with 9 or 18 holes. Players complete a hole by throwing a disc from a tee pad or area toward a target, throwing again from where the previous throw landed, until the target is reached. Usually, the number of throws a player uses to reach each target is tallied, and players seek to complete each hole in the lowest number of total throws.

In the game of cricket, a googly refers to a type of delivery bowled by a right-arm leg spin bowler. The googly is a variation of the typical leg spin type of delivery, in that the cricket ball is presented from the bowler's hand in such a way that once the ball pitches, it deviates in the opposite direction of a leg spinning type of delivery. It has also been colloquially and affectionately referred to as the wrong'un, Bosie or Bosey, with those latter two eponyms referring to Bernard Bosanquet, the bowler who initially discovered and began using the googly.

A topspinner is a type of delivery bowled by a cricketer bowling either wrist spin or finger spin. In either case, the bowler imparts the ball with top spin by twisting it with his or her fingers prior to delivery. In both cases, the topspinner is the halfway house between the stock delivery and the wrong'un - in the wrist spinner's case his googly, and in the finger spinner's case his doosra.

Fastball

The fastball is the most common type of pitch thrown by pitchers in baseball and softball. "Power pitchers," such as former American major leaguers Nolan Ryan and Roger Clemens, rely on speed to prevent the ball from being hit, and have thrown fastballs at speeds of 95–105 miles per hour (153–169 km/h) (officially) and up to 108.1 miles per hour (174.0 km/h) (unofficially). Pitchers who throw more slowly can put movement on the ball, or throw it on the outside of home plate where batters can't easily reach it.

Curveball Type of pitch in baseball

In baseball and softball, the curveball is a type of pitch thrown with a characteristic grip and hand movement that imparts forward spin to the ball, causing it to dive as it approaches the plate. Varieties of curveball include the 12–6 curveball, power curveball, and the knuckle curve. Its close relatives are the slider and the slurve. The "curve" of the ball varies from pitcher to pitcher.

Four-seam fastball Baseball pitch

A four-seam fastball, also called a rising fastball, a four-seamer, or a cross-seam fastball, is a pitch in baseball. It is a member of the fastball family of pitches and is usually the hardest ball thrown by a pitcher. The name of the pitch derives from the fact that with every rotation of the ball as it is thrown, four seams come into view. A few pitchers at the major league level can sometimes reach a pitch speed of up to 100 mph. It is often compared with the two-seam fastball.

Circle changeup Baseball pitch

In baseball, a circle changeup is a pitch thrown with a grip that includes a circle formation, hence the name circle changeup. The circle is formed by making a circle with the index finger, holding the thumb at the bottom of the ball parallel to the middle finger and holding the ball far out in the hand. The ball is thrown turning the palm out.

In baseball, an off-speed pitch is a pitch thrown at a slower speed than a fastball. Breaking balls and changeups are the two most common types of off-speed pitches. Very slow pitches which require the batter to provide most of the power on contact through bat speed are known as "junk" and include the knuckleball and the Eephus pitch, a sort of extreme changeup. The specific goals of off-speed pitches may vary, but in general they are used to disrupt the batter's timing, thereby lessening his chances of hitting the ball solidly or at all. Virtually all professional pitchers have at least one off-speed pitch in their repertoire. Despite the fact that most of these pitches break in some way, batters are sometimes able to anticipate them due to hints that the pitcher gives, such as changes in arm angle, arm speed, or placement of fingers.

In tennis, a grip is a way of holding the racquet in order to hit shots during a match. The three most commonly used conventional grips are: the Continental, the Eastern and the Semi-Western. Most players change grips during a match depending on what shot they are hitting.

Forehand

The forehand in tennis and other racket sports such as table tennis, squash and badminton is a shot made by swinging the racket across one's body with the hand moving palm-first. In tennis, except in the context of the phrase forehand volley, the term refers to a type of groundstroke—a stroke in which the ball has bounced before it is struck. It contrasts with the backhand, the other type of groundstroke. For a right-handed player, the forehand is a stroke that begins on the right side of the body, continues across the body as contact is made with the ball, and ends on the left side of the body. It is considered the easiest shot to master, perhaps because it is the most natural stroke. Beginners and advanced players often have better forehands than any other shots and use it as a weapon.

In tennis, there are a variety of types of shots which can be categorized in various ways. The grip you place on will help you have different types of shots, the lower your grip means that the ball is most likely going to be a ground stroke. According to William T. Tilden, "All tennis strokes, should be made with the body' at right angles to the net, with the shoulders lined up parallel to the line of flight of the ball ." The serve is the opening shot of a point. Groundstrokes are hit after the ball has already bounced, and can be either forehands or backhands depending on which direction the racket is swung relative to the body. A lob is a groundstroke hit well over the head of an opponent who is positioned at the net. A passing shot is a groundstroke that is hit out of reach of an opponent at the net far to his left or right. A cross-court shot is a shot hit from the left side of one player's court to the left side of the other player's court, so that it crosses the lengthwise centerline of the court. A down-the-line shot is one that is hit more or less parallel to, and near to, one of the sidelines, so that it never crosses the centerline.

A gyroball is a type of baseball pitch used primarily by players in Japan. It is thrown with a spiral-like spin, so that there is no Magnus force on the ball as it arrives at home plate. The gyroball is sometimes confused with the shuuto, another pitch used in Japan.

Wrist spin Type of spin bowling in cricket

Wrist spin is a type of bowling in the sport of cricket. It refers to the cricket technique and specific hand movements associated with imparting a particular direction of spin to the cricket ball. The other spinning technique, usually used to spin the ball in the opposite direction, is finger spin. Wrist spin is bowled by releasing the ball from the back of the hand, so that it passes over the little finger. Done by a right-handed bowler, this imparts an anticlockwise rotation to the ball, as seen from the bowler's perspective; a left-handed wrist spinner rotates the ball clockwise.

Finger spin is a type of bowling in the sport of cricket. It refers to the cricket technique and specific hand movements associated with imparting a particular direction of spin to the cricket ball. The other spinning technique, generally used to spin the ball in the opposite direction, is wrist spin. Although there are exceptions, finger spinners generally turn the ball less than wrist spinners. However, because the technique is simpler and easier to master, finger spinners tend to be more accurate.

Topspin

In ball sports, topspin is a property of a ball that rotates forwards as it is moving. Topspin on a ball propelled through the air imparts a downward force that causes the ball to drop, due to its interaction with the air. Topspin is the opposite of backspin.

In the sport of ten-pin bowling, there are many different ways in which to deliver the bowling ball in order to advance it toward the pins in an accurate and powerful manner. Generally, there are three basic forms of 10-pin bowling. The most basic form is known as stroking, which is the most classic form. The most powerful form is known as cranking, which imparts great leverage and maximum rotation on the ball, but sacrifices accuracy. In between the two is the domain of the tweener, who has characteristics of both, but does not truly fit into either category. A well-known variant of "tweening" is the power stroker.

The carrom ball is a style of spin bowling delivery used in cricket. The ball is released by flicking it between the thumb and a bent middle finger in order to impart spin. Though the delivery was first brought in use in early 1940s, it was re-introduced by Ajantha Mendis in 2008 as well as by Indian spinner Ravichandran Ashwin later. Varun Chakravarthy is among the newer players to use it.

Golf swing

The golf swing is the action by which players hit the ball in the sport of golf. The golf swing is a complex motion involving the whole body; the technicalities of the swing are known as golf stroke mechanics.

In badminton, a grip is a way of holding the racket in order to hit shots during a match. The most commonly used grip is the orthodox forehand grip. Most players change grips during a rally depending on whether it is a forehand or backhand shot. A grip is also the wrapping around the handle of the racket. There are many types and varieties of grips; the texture, thickness, color, material and surface are all factors that make grips unique.

References

  1. Frisbee: a Practitioner’s Manual and Definitive Treatise, Stancil E. D. Johnson, ISBN   978-0-911104-53-0, 1975
  2. "Disc Golf Review". Throwing sidearm. Archived from the original on January 7, 2015. Retrieved September 1, 2015.CS1 maint: discouraged parameter (link)