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An ordered example issue from the extended Straubing\u2013Th\u00e9rien hierarchy of regular languages is also shown to provide a positive example for the inequality [Formula: see text].<\/jats:p>","DOI":"10.1142\/s0218196716500648","type":"journal-article","created":{"date-parts":[[2016,10,4]],"date-time":"2016-10-04T09:52:37Z","timestamp":1475574757000},"page":"1483-1495","source":"Crossref","is-referenced-by-count":3,"title":["Reducibility vs. definability for pseudovarieties of semigroups"],"prefix":"10.1142","volume":"26","author":[{"given":"J.","family":"Almeida","sequence":"first","affiliation":[{"name":"Departamento de Matem\u00e1tica, Faculdade de Ci\u00eancias, Centro de Mathematica da Universidade do Porto, Rua do Campo Alegre, 687, 4169-007 Porto, Portugal"}]},{"given":"O.","family":"Kl\u00edma","sequence":"additional","affiliation":[{"name":"Department of Mathematics and Statistics, Masaryk University, Kotl\u00e1\u0159sk\u00e1 2, 611 37 Brno, Czech Republic"}]}],"member":"219","published-online":{"date-parts":[[2016,11,13]]},"reference":[{"key":"S0218196716500648BIB001","doi-asserted-by":"publisher","DOI":"10.2307\/2275184"},{"key":"S0218196716500648BIB002","doi-asserted-by":"publisher","DOI":"10.1142\/9789812831644"},{"key":"S0218196716500648BIB003","doi-asserted-by":"publisher","DOI":"10.1142\/S0218196799000163"},{"key":"S0218196716500648BIB004","doi-asserted-by":"publisher","DOI":"10.1142\/9789812776884_0009"},{"key":"S0218196716500648BIB005","doi-asserted-by":"publisher","DOI":"10.1007\/1-4020-3817-8_1"},{"key":"S0218196716500648BIB006","doi-asserted-by":"crossref","first-page":"445","DOI":"10.4171\/pm\/1792","volume":"64","author":"Almeida J.","year":"2007","journal-title":"Portugal. 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