@article{VMUMM_1989_2_a9,
     author = {L. A. Skornyakov},
     title = {Invertible elements of semirelatives and relatives},
     journal = {Vestnik Moskovskogo universiteta. Matematika, mehanika},
     pages = {37--40},
     publisher = {mathdoc},
     number = {2},
     year = {1989},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/VMUMM_1989_2_a9/}
}