{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,11]],"date-time":"2026-03-11T16:36:19Z","timestamp":1773246979168,"version":"3.50.1"},"reference-count":14,"publisher":"World Scientific Pub Co Pte Lt","issue":"06","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Int. J. Algebra Comput."],"published-print":{"date-parts":[[1999,12]]},"abstract":"<jats:p> Much of the structure theory of inverse semigroups is based on constructing arbitrary inverse semigroups from groups and semilattices. It is known that E-unitary (or proper) inverse semigroups may be described as P-semigroups (McAlister), or inverse subsemigroups of semidirect products of a semilattice by a group (O'Carroll) or C<jats:sub>u<\/jats:sub>-semigroups built over an inverse category acted upon by a group (Margolis and Pin). On the other hand, every inverse semigroup is known to have an E-unitary inverse cover (McAlister). <\/jats:p><jats:p> The aim of this paper is to develop a similar theory for proper weakly left ample semigroups, a class with properties echoing those of inverse semigroups. We show how the structure of semigroups in this class is based on constructing semigroups from unipotent monoids and semilattices. The results corresponding to those of McAlister, O'Carroll and Margolis and Pin are obtained. <\/jats:p>","DOI":"10.1142\/s0218196799000412","type":"journal-article","created":{"date-parts":[[2002,7,27]],"date-time":"2002-07-27T07:05:54Z","timestamp":1027753554000},"page":"721-739","source":"Crossref","is-referenced-by-count":27,"title":["PROPER WEAKLY LEFT AMPLE SEMIGROUPS"],"prefix":"10.1142","volume":"09","author":[{"given":"GRACINDA M. S.","family":"GOMES","sequence":"first","affiliation":[{"name":"Centro de \u00c1lgebra, Universidade de Lisboa, Av. Prof Gama Pinto, 2, 1649-003 Lisboa, Portugal"},{"name":"Departamento de Matem\u00e1tica, Faculdade de Ci\u00eancias, Universidade de Lisboa, 1746-016 Lisboa, Portugal"}]},{"given":"VICTORIA","family":"GOULD","sequence":"additional","affiliation":[{"name":"Department of Mathematics, University of York, Heslington, York, Y010\u00a05DD, UK"}]}],"member":"219","published-online":{"date-parts":[[2011,11,20]]},"reference":[{"key":"p_2","doi-asserted-by":"publisher","DOI":"10.1017\/S0017089500031840"},{"key":"p_3","doi-asserted-by":"publisher","DOI":"10.1093\/qmath\/28.3.285"},{"key":"p_4","doi-asserted-by":"publisher","DOI":"10.1112\/blms\/22.4.353"},{"key":"p_5","doi-asserted-by":"publisher","DOI":"10.1016\/0022-4049(92)90066-O"},{"key":"p_6","doi-asserted-by":"publisher","DOI":"10.1017\/S0017089500009873"},{"key":"p_7","first-page":"1","volume":"5","author":"Fountain J.","year":"1994","journal-title":"Portugaliae Math."},{"key":"p_8","doi-asserted-by":"publisher","DOI":"10.1006\/jabr.1999.7871"},{"key":"p_9","doi-asserted-by":"publisher","DOI":"10.1080\/00927879908826450"},{"key":"p_11","doi-asserted-by":"publisher","DOI":"10.1016\/0021-8693(87)90046-9"},{"key":"p_12","first-page":"227","volume":"192","author":"McAlister D. B.","year":"1974","journal-title":"Trans. Amer. Math. Soc."},{"key":"p_13","doi-asserted-by":"publisher","DOI":"10.1090\/S0002-9947-74-99950-4"},{"key":"p_14","doi-asserted-by":"publisher","DOI":"10.1017\/S2040618500034286"},{"key":"p_15","doi-asserted-by":"publisher","DOI":"10.1016\/0021-8693(76)90023-5"},{"key":"p_17","doi-asserted-by":"publisher","DOI":"10.1016\/0022-4049(87)90108-3"}],"container-title":["International Journal of Algebra and Computation"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.worldscientific.com\/doi\/pdf\/10.1142\/S0218196799000412","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2019,8,6]],"date-time":"2019-08-06T17:55:34Z","timestamp":1565114134000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.worldscientific.com\/doi\/abs\/10.1142\/S0218196799000412"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1999,12]]},"references-count":14,"journal-issue":{"issue":"06","published-online":{"date-parts":[[2011,11,20]]},"published-print":{"date-parts":[[1999,12]]}},"alternative-id":["10.1142\/S0218196799000412"],"URL":"https:\/\/doi.org\/10.1142\/s0218196799000412","relation":{},"ISSN":["0218-1967","1793-6500"],"issn-type":[{"value":"0218-1967","type":"print"},{"value":"1793-6500","type":"electronic"}],"subject":[],"published":{"date-parts":[[1999,12]]}}}