TY  - BOOK
AU  - Gronau, Hans-Dietrich ed.
AU  -  Langmann ,Hanns-Heinrich.ed.
AU  -  Schleicher, Dierk,ed.
TI  - 50th IMO - 50 years of International Mathematical Olympiads
SN  - 9783642145643
PY  - 2011///
CY  - Heidelberg
PB  - Springer
KW  - Mathematics --Problems, exercises, etc.
KW  -  Mathematics --Competitions
ER  -