@article{SF_1990__40_1_135004,
     author = {B. M. Vernikov},
     title = {Dualities in lattices of semigroup varieties.},
     journal = {Semigroup forum},
     pages = {59--76},
     publisher = {mathdoc},
     volume = {40},
     number = {1},
     year = {1990},
     zbl = {0687.20055},
     url = {http://geodesic.mathdoc.fr/item/SF_1990__40_1_135004/}
}