@article{DAN_1961_139_6_a13,
     author = {V. I. Varshavskii},
     title = {On the complexity of networks with depth two formulated from threshold elements},
     journal = {Doklady Akademii Nauk},
     pages = {1325--1328},
     publisher = {mathdoc},
     volume = {139},
     number = {6},
     year = {1961},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1961_139_6_a13/}
}