@misc{AMUC_1980__37_185785,
     title = {[unknown]},
     journal = {Acta mathematica Universitatis Comenianae},
     pages = {91--92},
     year = {1980},
     volume = {37},
     url = {http://geodesic.mathdoc.fr/item/AMUC_1980__37_185785/}
}