@article{MO_2002_22_3_a4,
     author = {A. Yu. Evnin},
     title = {Problems of the {Putnam} {Olympiads}},
     journal = {Matemati\v{c}eskoe obrazovanie},
     pages = {86--102},
     publisher = {mathdoc},
     volume = {22},
     number = {3},
     year = {2002},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MO_2002_22_3_a4/}
}