TY  - BOOK
AU  - Shklarsky,D.O.
AU  - Chentzov,N.N.
AU  - Yaglom,I.M.
TI  - The USSR Olympiad problem book: selected problems and theorems of elementary mathematics 
SN  - 0-486-27709-7
PY  - 1994///
CY  - New York
PB  - Dover
KW  - Matemáticas
KW  - Problemas, ejercicios, etc
ER  -