@article{SM_2017_208_1_a3,
     author = {D. Z. Kagan},
     title = {Nontrivial pseudocharacters on groups with one defining relation and nontrivial centre},
     journal = {Sbornik. Mathematics},
     pages = {75--89},
     publisher = {mathdoc},
     volume = {208},
     number = {1},
     year = {2017},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SM_2017_208_1_a3/}
}