@article{IVM_1962_3_a18,
     author = {A. I. Cheremisin},
     title = {Betweenness rings},
     journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika},
     pages = {158--163},
     publisher = {mathdoc},
     number = {3},
     year = {1962},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/IVM_1962_3_a18/}
}