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References
- 1 2 3 4 5 6 John Fountain (2002). "An introduction to covers for semigrops". In Gracinda M. S. Gomes (ed.). Semigroups, Algorithms, Automata and Languages. World Scientific. pp. 167–168. ISBN 978-981-277-688-4. preprint
- ↑ Mitsch, H. (2009). "Subdirect products of E–inversive semigroups". Journal of the Australian Mathematical Society. 48: 66–78. doi: 10.1017/S1446788700035199 .
- ↑ Manoj Siripitukdet and Supavinee Sattayaporn Semilattice Congruences on E-inversive Semigroups Archived 2014-09-03 at the Wayback Machine , NU Science Journal 2007; 4(S1): 40 - 44
- ↑ G. Thierrin (1955), 'Demigroupes inverses et rectangularies', Bull. Cl. Sci. Acad. Roy. Belgique 41, 83-92.
- ↑ Weipoltshammer, B. (2002). "Certain congruences on E-inversive E-semigroups". Semigroup Forum . 65 (2): 233–248. doi:10.1007/s002330010131.
- ↑ Fountain, J.; Hayes, A. (2014). "E ∗-dense E-semigroups". Semigroup Forum . 89: 105–124. doi:10.1007/s00233-013-9562-z. preprint
