Gerla, Giangiacomo L-subsemigroups of a free semigroup. (English) Zbl 0631.20048 Rend. Mat. Appl., VII. Ser. 5, No. 1-2, 19-28 (1985). The paper deals with certain meet-complete lattices of subsemigroups of a free semigroup. Such a lattice can be connected with a fuzzy or L-fuzzy semigroup [cf. the author, Ric. Mat. 33, 53-62 (1984; Zbl 0582.20037)] on a given free semigroup (the lattice of a-cuts). Considering lattices of free, pure, very pure, left unitary, right unitary and unitary semigroups [cf. G. Lallement, Semigroups and combinatorial applications (1979; Zbl 0421.20025)], the author leads to suitable conditions for the respective fuzzy semigroups. Reviewer: J.Drewniak Cited in 1 ReviewCited in 3 Documents MSC: 20M05 Free semigroups, generators and relations, word problems 08A30 Subalgebras, congruence relations Keywords:pure semigroup; unitary semigroup; meet-complete lattices of subsemigroups; free semigroup; L-fuzzy semigroup Citations:Zbl 0582.20037; Zbl 0421.20025 PDF BibTeX XML Cite \textit{G. Gerla}, Rend. Mat. Appl., VII. Ser. 5, No. 1--2, 19--28 (1985; Zbl 0631.20048) OpenURL