Barber

Last updated
Barber, Hairdresser
Barbero-afeitado-clasico-compressor.jpg
Occupation
NamesBarber, hairdresser
Occupation type
Vocation
Description
Fields of
employment
Barbershops, hair salons, hairdressing salons

A barber is a person whose occupation is mainly to cut, dress, groom, style and shave hair or beards. A barber's place of work is known as a barbershop or the barber's. Barbershops have been noted places of social interaction and public discourse since at least classical antiquity. In some instances, barbershops were also public forums. They were the locations of open debates, voicing public concerns, and engaging citizens in discussions about contemporary issues.

Contents

In previous times, barbers (known as barber surgeons) also performed surgery and dentistry. [1] With the development of safety razors and the decreasing prevalence of beards in Anglophonic cultures, most barbers now specialize in cutting men's scalp hair as opposed to facial hair.

Names

A barber shop along the Ruoholahdenkatu street in Kamppi, Helsinki, Finland 2018-04-21-12-25-25-IMG 7258 (46219375424).jpg
A barber shop along the Ruoholahdenkatu street in Kamppi, Helsinki, Finland
A barber practicing a haircut in Tokyo, Japan

In modern times, the term "barber" is used both as a professional title and to refer to hairdressers who specialize in men's hair. Historically, all hairdressers were considered barbers. In the 20th century, the profession of cosmetology branched off from barbering, and today hairdressers may be licensed as either barbers or cosmetologists. Barbers differ with respect to where they work, which services they are licensed to provide, and what name they use to refer to themselves. Part of this terminology difference depends on the regulations in a given location.

In the early 1900s, an alternative word for barber, "chirotonsor", came into use in the U.S. [2]

Different states in the US vary on their labor and licensing laws. For example, in Maryland and Pennsylvania, a cosmetologist cannot use a straight razor, strictly reserved for barbers. In contrast, in New Jersey both are regulated by the State Board of Cosmetology and there is no longer a legal difference in barbers and cosmetologists, as they are issued the same license and can practice both the art of straight razor shaving, coloring, other chemical work and haircutting if they choose.[ citation needed ]

In Australia, during the mid to late 20th century, the official term for a barber was men's hairdresser; barber was only a popular title for men's hairdressers. During this time, most would work in either a barbershop or hairdressing salon.

History

Boiotian Greek painted terracotta figure dating between c. 500 and c. 475 BCE, currently held in the Museum of Fine Arts, showing a barber cutting a man's hair Boiotian Greek painted terracotta figure of a barber cutting a man's hair.jpg
Boiotian Greek painted terracotta figure dating between c. 500 and c. 475 BCE, currently held in the Museum of Fine Arts, showing a barber cutting a man's hair

Antiquity

The barber's trade has a long history: razors have been found among relics of the Bronze Age (around 3500 BC) in Egypt. The first barbering services were performed by Egyptians in 5000 BC with instruments they had made from oyster shells or sharpened flint. [3] In ancient Egyptian culture, barbers were highly respected individuals. Priests and men of medicine are the earliest recorded examples of barbers. [4] In addition, the art of barbering played a significant role across continents. Mayan, Aztec, Iroquois, Norse and Mongolian cultures utilized shave art as a way to distinguish roles in society and wartime. [5] Men in Ancient Greece would have their beards, hair, and fingernails trimmed and styled by the κουρεύς (cureus), in an agora (market place) which also served as a social gathering for debates and gossip. The barbers used a rough cloth (ὠμόλινον) on their shoulders to keep the hairs off their dresses. There were also female barbers (κουρεύτριαι). [6]

Barbering was introduced to Rome by the Greek colonies in Sicily in 296 BC,[ citation needed ] and barbershops (Latin : tonstrīna , lit. "clipperies") quickly became very popular centers for daily news and gossip. [7] A morning visit to the barber ( tonsor ) became a part of the daily routine, as important as the visit to the public baths, and a young man's first shave ( tonsura ) was considered an essential part of his coming of age ceremony.[ citation needed ] Roman barbers employed rudimentary mirrors and wielded combs, razors, scissors, curling irons, specialized tools for beard removal and pomata to remove unwanted hair elsewhere. [7] A few Roman barbers became wealthy and influential, running shops that were favorite public locations of high society. Most, however, were simple tradesmen who owned small storefronts or worked in the streets for low prices.

Middle Ages

"A barber getting ready to shave the face of a seated customer.", c. 1801. A barber getting ready to shave the face of a seated custome Wellcome V0019707.jpg
"A barber getting ready to shave the face of a seated customer.", c. 1801.

Starting from the Middle Ages, barbers often served as surgeons and dentists. In addition to haircutting, hairdressing, and shaving, barbers performed surgery, bloodletting and leeching, fire cupping, enemas, and the extraction of teeth; earning them the name "barber surgeons". [8] Barber-surgeons began to form powerful guilds such as the Worshipful Company of Barbers in London. Barbers received higher pay than surgeons until surgeons were entered into British warships during naval wars. Some of the duties of the barber included neck manipulation, cleansing of ears and scalp, draining of boils, fistula and lancing of cysts with wicks.

Modernity

Barbershop in Bucharest [?]1842. The barbershop also provides an opportunity for social contacts. Bucharest Barbershop 1842.jpg
Barbershop in Bucharest ≈1842. The barbershop also provides an opportunity for social contacts.

Barbershops were influential at the turn of the 19th century in the United States as African American businesses that helped to develop African American culture and economy. According to Trudier Harris, "In addition to its status as a gathering place, the black barbershop also functioned as a complicated and often contradictory microcosm of the larger world. It is an environment that can bolster egos and be supportive as well as a place where phony men can be destroyed, or at least highly shamed, from participation in verbal contests and other contests of skill. It is a retreat, a haven, an escape from nagging wives and the cares of the world. It is a place where men can be men. It is a place, in contrast to Gordone's bar, to be somebody." [9] Barbershops from black barbers at first mostly served wealthy Caucasians. In the later part of the century they opened barbershops in black communities for serving black people. [10]

The average shop cost $20 to equip in 1880. It was about ten by twelve feet. A hair cut in 1880 would cost five or ten cents and shaving cost three cents. [11]

A hair dryer in barbershop Blow hair dryer.jpg
A hair dryer in barbershop
A barber shop in Essex County, Ontario, [ca. 1900], with the photographer visible in the mirror at the back. At the barber shop, Essex County (I0015263).tiff
A barber shop in Essex County, Ontario, [ca. 1900], with the photographer visible in the mirror at the back.

In the late 19th and early 20th century, barbershops became a common business in the United States where people would go to have their hair cut by a professional barber with good equipment. People would also play board games, talk about recent events, or gossip. [12] [13] They have also occasionally been used for public debates or voicing public concerns. [14]

Most modern barbershops have special barber chairs, and special equipment for rinsing and washing hair. In some barbershops, people can read magazines or watch TV while the barber works.

An Iranian barber shaping his costumer's beard in Ahvaz, Iran [?]2022 Iranian barber.jpg
An Iranian barber shaping his costumer's beard in Ahvaz, Iran ≈2022

Despite the economic recession in 2008, the barbershop industry has seen continued positive growth. In 2018 there was a trial that had barbers check high blood pressure in barbershops and have a pharmacist meet and treat the patient in the barbershop, with positive results. [15]

In 2018, Arthur Rubinoff opened a museum with barber poles and antique barber equipment in Manhattan. [16]

The barber Sam Mature, whose interview with Studs Terkel was published in Terkel's 1974 book Working , says "A man used to get a haircut every couple weeks. Now he waits a month or two, some of 'em even longer than that. A lot of people would get manicured and fixed up every week. Most of these people retired, moved away, or died. It's all on account of long hair. You take old-timers, they wanted to look neat, to be presentable. Now people don't seem to care too much."

Given their importance as social hubs in certain cultures, barbershops have been used in educational campaigns. These include the U.S. literacy project Barbershop Books, [17] which sets up reading stations in barbershops to promote a culture of reading among African American boys. [18] Public health researchers have also explored barbershops as a venue for sexual health education. [19]

Barber schools

In 1893, A. B. Moler of Chicago established a school for barbers. This was the first institution of its kind in the world, and its success was apparent from its very start. It stood for higher education in the ranks, and the parent school was rapidly followed by branches in nearly every principal city of the United States. In the beginning of barber schools, only the practical work of shaving, hair-cutting, facial treatments, etc., was taught as neither the public nor the profession was ready to accept scientific treatments of hair, skin and scalp. Not until about 1920 was much effort made to professionalize the work. [4]

Training to be a barber is achieved through various means around the world. In the US, barber training is carried out at "barber schools".[ citation needed ]

Cost – Many states require a barber license in order to practice barbering professionally. The cost of barber school varies from state to state, and also from metro area to metro area. Schools in larger metropolitan areas tend to cost more than those located in more rural towns. Brand names can also affect the cost of barber school. Most barber schools cost between $6,500 and $10,000 to complete. Because each state has different minimums for training hours, the length and cost of the program can vary accordingly. Some schools' tuition includes supplies and textbooks, whereas others do not. Barber license exam fees typically range from $50 to $150.[ citation needed ]

Length – Most states require the same amount of training hours for barbers as they do for cosmetologists. The number of hours required ranges from 800 to 2,000 training hours, depending on the state's licensing requirements. Most programs can be completed in 15 months or fewer.[ citation needed ]

Curriculum – The barber school curriculum consists of hair cutting, coloring and styling for men's hair and women's short hair. Chemical processes such as bleaching, dyeing, lightening and relaxing hair may also be taught. All cosmetology disciplines learn safety and sanitation best practices. Barber students can expect to learn some elements of anatomy, physiology, bacteriology and some small elements of pharmacology. It also teaches facial hair techniques, including traditional and modern shaves. Generally barber programs touch on scalp massage and treatments. Advanced barber training may include custom shave designs. It is more common in barbering schools than other cosmetology disciplines to get some business and ethics education, since entrepreneurship is especially common in the barbering trade with many professionals choosing to open their own barbershops. All the skills learned in barber school will be tested at the board exams, which typically feature a written and practical exam.[ citation needed ]

Barber's pole

A red, white and blue striped pole Barber Shop Pole.jpg
A red, white and blue striped pole

The barber pole, featuring blue, red and white spiraling stripes, symbolizes different aspects of the craft. It is a symbol from the time when barbers used to perform medical procedures. The white and red stripes represent bandages and blood while the blue stripes represent veins. The pole may be stationary or may rotate, often with the aid of an electric motor. [21] [22] A spinning barber pole creates a visual illusion, in which the stripes appear to be traveling up or down the length of the pole, [23] rather than around it. [24] [25]

In the United States, the blue stripe is also sometimes used to match the flag. [10] [26] [27] In South Korea, barber's poles are used both for actual barbershops and for brothels. [28] [29] In Forest Grove, Oregon, the "World's Tallest Barber Shop Pole" measures 72 feet (22 m). [30]

Because of its bright bands and colors, the redbanded rockfish Sebastes babcocki is referred to as "barber pole". Other pseudonyms include bandit, convict, canary, Hollywood, and Spanish flag. [31]

The phrase barber pole is derisive jargon in craps, and refers to the commingling of "gaming cheques of different denominations". Wagers that combine different denominations are "supposed to be stacked with the highest denomination at the bottom". [32] [33]

Equipment

The market for barber supplies is estimated to have revenue of around twenty billion dollars. The industry in the U.S. market is expected to grow by around 3% per year between 2017 and 2022.[ citation needed ]

Animals

The term "barbering" when applied to laboratory mice is a behavior where mice will use their teeth to pluck out hairs from the face of cage mates when they groom each other. It is practised by both male and female mice. The "barber" plucks the vibrissae of the recipient. The behavior is probably related to social dominance. [34]

See also

Related Research Articles

<span class="mw-page-title-main">Leg shaving</span> Cultural grooming practice

Leg shaving is the practice of removing leg hair by shaving the hair off using a razor or electric shaver. In addition, some people remove leg hair using waxing, sugaring, depilatories, epilators or other depilation devices, or lasers, but shaving remains the least expensive and one of the least painful methods.

<span class="mw-page-title-main">Hair removal</span> Temporary body hair removal

Hair removal is the deliberate removal of body hair or head hair. This process is also known as epilation or depilation.

<span class="mw-page-title-main">Shaving</span> Removal of hair with a razor or others bladed implement

Shaving is the removal of hair, by using a razor or any other kind of bladed implement, to slice it down—to the level of the skin or otherwise. Shaving is most commonly practiced by men to remove their facial hair and by women to remove their leg and underarm hair. A man is called clean-shaven if he has had his beard entirely removed.

<span class="mw-page-title-main">Worshipful Company of Barbers</span> Professional guild of the City of London

The Worshipful Company of Barbers is one of the livery companies of the City of London, and ranks 17th in precedence.

<span class="mw-page-title-main">Cosmetology</span> Study and application of beauty treatment

Cosmetology is the study and application of beauty treatment. Branches of specialty include hairstyling, skin care, cosmetics, manicures/pedicures, non-permanent hair removal such as waxing and sugaring, and permanent hair removal processes such as electrology and intense pulsed light (IPL).

<span class="mw-page-title-main">Razor</span> Device to remove body hair

A razor is a bladed tool primarily used in the removal of body hair through the act of shaving. Kinds of razors include straight razors, safety razors, disposable razors, and electric razors.

<span class="mw-page-title-main">Safety razor</span> Shaving implement

A safety razor is a shaving implement with a protective device positioned between the edge of the blade and the skin. The initial purpose of these protective devices was to reduce the level of skill needed for injury-free shaving, thereby reducing the reliance on professional barbers.

<span class="mw-page-title-main">Head shaving</span> Shaving the hair from a persons head

Head shaving is a form of body modification which involves shaving the hair from a person's head. People throughout history have shaved all or part of their heads for diverse reasons including aesthetics, convenience, culture, fashion, practicality, punishment, a rite of passage, religion, or style.

<span class="mw-page-title-main">Hairdresser</span> Person whose occupation is to cut or style hair

A hairdresser is a person whose occupation is to cut or style hair in order to change or maintain a person's image. This is achieved using a combination of hair coloring, haircutting, and hair texturing techniques. A hairdresser may also be referred to as a 'barber' or 'hairstylist'.

<span class="mw-page-title-main">Electric shaver</span> Razor with an electrically powered rotating or oscillating blade

An electric shaver is a razor with an electrically powered rotating or oscillating blade. The electric shaver usually does not require the use of shaving cream, soap, or water. The razor may be powered by a small DC motor, which is either powered by batteries or mains electricity. Many modern ones are powered using rechargeable batteries. Alternatively, an electro-mechanical oscillator driven by an AC-energized solenoid may be used. Some very early mechanical shavers had no electric motor and had to be powered by hand, for example by pulling a cord to drive a flywheel.

<span class="mw-page-title-main">Pseudofolliculitis barbae</span> Medical condition

Pseudofolliculitis barbae (PFB) is a type of irritant folliculitis that commonly affects people who have curly or coarse facial hair. It occurs when hair curls back into the skin after shaving, causing inflammation, redness, and bumps. This can lead to ingrown hairs, scarring, and skin discoloration. PFB can be treated with various methods, including changing shaving habits, using topical creams or ointments, and undergoing laser hair removal. Prevention measures include proper shaving techniques, using sharp razors, and avoiding too close a shave.

<span class="mw-page-title-main">Straight razor</span> Knife used to remove body hair

A straight razor is a razor with a blade that can fold into its handle. They are also called open razors and cut-throat razors. The predecessors of the modern straight razors include bronze razors, with cutting edges and fixed handles, produced by craftsmen from Ancient Egypt during the New Kingdom. Solid gold and copper razors were also found in Ancient Egyptian tombs dating back to the 4th millennium BC.

<span class="mw-page-title-main">Barber's pole</span> Type of sign

A barber's pole is a type of sign used by barbers to signify the place or shop where they perform their craft. The trade sign is, by a tradition dating back to the Middle Ages, a staff or pole with a helix of colored stripes. The pole may be stationary or may rotate, often with the aid of an electric motor.

<span class="mw-page-title-main">Shaving brush</span> Tool to make and apply shaving soap or cream

A shaving brush or shave brush is a small brush with a handle parallel to the bristles used to make lather from shaving soap or shaving cream and apply it to the face when shaving. Shave brushes are often decorative; antique handles are often made from materials such as ivory or even gold, though the bristle load may be composed of any number of natural or synthetic materials. The shave brush is used most often today by "wet shavers" in tandem with a single- or double-edged safety razor or a straight razor. However, this is not always the case, as shavers of all varieties may employ the tool.

<i>The Barber of Seville</i> (1944 film) 1944 film by Shamus Culhane

The Barber of Seville is the tenth animated cartoon short subject in the Woody Woodpecker series. Released theatrically on April 22, 1944, the film was produced by Walter Lantz Productions and distributed by Universal Pictures.

<span class="mw-page-title-main">Roman hairstyles</span> Hairstyles in ancient Rome

Hairstyle fashion in Rome was ever changing, and particularly in the Roman Imperial Period there were a number of different ways to style hair. As with clothes, there were several hairstyles that were limited to certain people in ancient society. Styles are so distinctive they allow scholars today to create a chronology of Roman portraiture and art; we are able to date pictures of the empresses on coins or identify busts depending on their hairstyles.

<span class="mw-page-title-main">Shaving soap</span> Hard soap that is used to produce lather with a shaving brush

Shaving soap is a hard soap that is used to produce lather with a shaving brush. The lather it produces is used to coat the face during shaving, softening the hair in preparation for shaving.

<span class="mw-page-title-main">Regular haircut</span> Simple hairstyle popular among males

A regularhaircut in Western fashion is a men's and boys' hairstyle featuring hair long enough to comb on top, with a defined or deconstructed side part, and back and sides that vary in length from short, semi-short, medium, long, to extra long. The style is also known by other names including taper cut, regular taper cut, side-part and standard haircut; as well as short back and sides, business-man cut and professional cut, subject to varying national, regional, and local interpretations of the specific taper for the back and sides.

<span class="mw-page-title-main">Shanghai-style barber shops in Hong Kong</span>

Shanghai-Style Barber Shop is a barber shop opened by a group of Shanghai barbers coming to Hong Kong mainly in the 1950s to give classical Shanghai haircuts. It is popular in Hong Kong among higher class people in the period of 1950s-1970s, offering a range of classical haircut until today. Other than hair-cutting, Shanghai style barber shops provide different unique services include trimming, massaging, nails clipping, etc. Despite the sunset of Shanghai style barber shop in Hong Kong in the modern days, it still attracts loyal customers, especially among males, and costs around HK$70 for a haircut and shave using traditional clippers.

<span class="mw-page-title-main">Pall Mall Barbers</span> Barber shop chain

Pall Mall Barbers is a barbershop chain with six locations in London and one in New York City. The company is owned and managed by Richard Marshall.

References

  1. Küskü, Elif Aslan (2022-01-01). "Examination of Scientific Revolution Medicine on the Human Body / Bilimsel Devrim Tıbbını İnsan Bedeni Üzerinden İncelemek". The Legends Journal of European History Studies.
  2. "On this day in Florida history - June 21, 1926 - Miami barbers don't want to be called 'chirotonsors'". Florida History Network. Retrieved 2020-12-07.
  3. "Barbering Timeline - National Barber Museum". www.nationalbarbermuseum.org. Retrieved 2018-06-17.
  4. 1 2 Moler, A.B.. "The barbers' manual." Internet Archive: Digital Library of Free Books, Movies, Music & Wayback Machine. The National Education Council of the Associated Master Barbers of America, 1 January 1928. Web. 19 March 2012. https://archive.org/stream/barbersmanual00mole#page/n29/mode/2up.
  5. Kuiper, A.C. "The Hair Etching Pen Guide, 14 April 2018. Web. 14 April 2018. https://www.royaletch.com/hair-etching-pen-guide/.
  6. Harry Thurston Peck, Harpers Dictionary of Classical Antiquities (1898), Tonsor
  7. 1 2 Chrisman, Oscar (1920), The Historical Child, Boston: Richard G. Badger, p. 235.
  8. "Surgeons and Surgical Spaces #The Barber's Shop". sciencemuseum.org.uk. Retrieved 2020-05-05.
  9. Harris, Trudier (Autumn 1979). "The Barbershop in Black Literature". Black American Literature Forum. 13 (3): 112–118. doi:10.2307/3041528. JSTOR   3041528.
  10. 1 2 "A Quick History Of Barbering | Austin, TX Barbershop". eighteeneight.com. 2017-10-16. Archived from the original on 2021-03-08. Retrieved 2018-06-18.
  11. "Barbering Timeline - National Barber Museum". www.nationalbarbermuseum.org. Retrieved 2018-06-18.
  12. Bliss, Jessica (2018-01-12). "Oprah for president? The buzz at Winfrey's barbershop in Nashville". The Tennessean. Retrieved 2018-06-17.
  13. "History Of Barbers". beardtrimandgroom.com. 27 September 2014. Archived from the original on 2021-07-11. Retrieved 2018-06-18.
  14. "coloradobarbers". coloradobarbers. Archived from the original on 2021-07-11. Retrieved 2018-06-18.
  15. Caroll, Aaron E. (2018-05-21). "What Barbershops Can Teach About Delivering Health Care". The New York Times . Retrieved 2018-06-18.
  16. Kilgannon, Corey (2018-05-04). "Barbering Is an Art". The New York Times . Retrieved 2018-06-18.
  17. "About Us – Barbershop Books". Barbershop Books. Retrieved 2018-08-14.
  18. Ro, Christine (2018-06-13). "Barbershop Books". Poets & Writers.
  19. Randolph, Schenita D.; Pleasants, Terrence; Gonzalez-Guarda, Rosa M. (November 2017). "Barber-led sexual health education intervention for Black male adolescents and their fathers". Public Health Nursing. 34 (6): 555–560. doi:10.1111/phn.12350. ISSN   1525-1446. PMID   28812306. S2CID   11564832.
  20. "Heritage Village | Snyder, Scurry County, Texas". historicscurrycounty.com. Retrieved 2018-06-19.
  21. "Barber Pole". Webster's New World College Dictionary. Cleveland: Wiley Publishing. 2010. Retrieved 14 November 2010.
  22. Smith, Kate. "Why Barber Poles are Red and White". Sensational Color. Archived from the original on 29 November 2010. Retrieved 14 November 2010.
  23. "Barber Pole Illusion". sandlotscience.com. Archived from the original on 28 November 2010. Retrieved 14 November 2010.
  24. Massaro, Dominic W., ed. (Spring 2007). "Book Reviews: What Are Musical Paradox and Illusion?" (PDF). American Journal of Psychology . 120 (1). University of California, Santa Cruz: 123–170, 124, 132. doi:10.2307/20445384. JSTOR   20445384.
  25. Carrella, Stefano; Iswandy, Kuncup; Lutz, Kai; King, Andreas (18–19 May 2010). "3D-Localization of Low-Power Wireless Sensor Nodes Based on AMR-Sensors in Industrial and AmI Applications" (CD-ROM). Sensoren und Messsysteme 2010. Vorträge der 15. ITG/GMA-Fachtagung. Nuremberg: Berlin Offenbach. ISBN   978-3-8007-3260-9 . Retrieved 14 November 2010.
  26. Burke, Joan (February 2005). "Management of Barber Pole Worm in Sheep and Goats in the Southern U.S" (PDF). Small Farms Research Update. Booneville, Arkansas: U.S. Department of Agriculture Dale Bumpers Small Farms Research Center. Archived from the original (PDF) on 5 March 2009. Retrieved 4 March 2010.
  27. Schoenian, Susan (15 February 2005). "Diseases: Worms". Sheep 101.
  28. Moon, Katharine Hyung-Sun (1997). Sex Among Allies: Military Prostitution in U.S.–Korea Relations. New York: Columbia University Press. p. 45. ISBN   978-0-231-10642-9 . Retrieved 14 November 2010.
  29. Trecker, Jamie (2007). Love and Blood: At the World Cup with the Footballers, Fans, and Freaks . Orlando: Houghton Mifflin Harcourt. p.  13. ISBN   978-0-15-603098-4 . Retrieved 14 November 2010. prostitution barber.
  30. Kirby, Doug; Smith, Ken; Wilkins, Mike (2010). "Forest Grove, Oregon: World's Tallest Barber Shop Pole". Novato, California: Roadside America. Retrieved 14 November 2010.
  31. "Redbanded rockfish". Alaska Fisheries Science Center. National Marine Fisheries Service National Oceanic and Atmospheric Administration . Retrieved 14 December 2010.
  32. Cameron, Scott (2010). "Craps Lingo". CasinoDealers. Retrieved 14 November 2010.
  33. "Crap Dictionary". World Casino Directory. 2010. Retrieved 14 November 2010.
  34. Sarna, JR; Dyck, RH; Whishaw, IQ (February 2000). "The Dalila effect: C57BL6 mice barber whiskers by plucking". Behavioural Brain Research . 108 (1): 39–45. CiteSeerX   10.1.1.519.7265 . doi:10.1016/S0166-4328(99)00137-0. PMID   10680755. S2CID   18334770.

Further reading