@article{ITA_2005__39_1_31_0,
     author = {Almeida, Jorge and Margolis, Stuart W. and Volkov, Mikhail V.},
     title = {The pseudovariety of semigroups of triangular matrices over a finite field},
     journal = {RAIRO - Theoretical Informatics and Applications - Informatique Th\'eorique et Applications},
     pages = {31--48},
     publisher = {EDP-Sciences},
     volume = {39},
     number = {1},
     year = {2005},
     doi = {10.1051/ita:2005002},
     mrnumber = {2132577},
     zbl = {1086.20029},
     language = {en},
     url = {http://archive.numdam.org/articles/10.1051/ita:2005002/}
}