@article{DAN_1961_139_5_a1,
     author = {Ya. P. Blank},
     title = {On translation surfaces of constant curvature},
     journal = {Doklady Akademii Nauk},
     pages = {1037--1039},
     publisher = {mathdoc},
     volume = {139},
     number = {5},
     year = {1961},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1961_139_5_a1/}
}