@article{IVM_1966_6_a15,
     author = {V. V. Rozen},
     title = {Restrictive bisemigroups associated with generalized heaps},
     journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika},
     pages = {144--151},
     publisher = {mathdoc},
     number = {6},
     year = {1966},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/IVM_1966_6_a15/}
}