@article{SF_1990__41_2_135034,
     author = {S.S. Yu},
     title = {Quasi-completely right disjunctive languages.},
     journal = {Semigroup forum},
     pages = {39--48},
     publisher = {mathdoc},
     volume = {41},
     number = {2},
     year = {1990},
     zbl = {0695.20039},
     url = {http://geodesic.mathdoc.fr/item/SF_1990__41_2_135034/}
}