@article{MZM_2013_93_6_a4,
     author = {V. A. Krasnov},
     title = {Real {Four-Dimensional} $\mathit{GM}${-Triquadrics}},
     journal = {Matemati\v{c}eskie zametki},
     pages = {844--852},
     publisher = {mathdoc},
     volume = {93},
     number = {6},
     year = {2013},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_2013_93_6_a4/}
}