Autori: D.M. Bătineţu-Giurgiu; Marin Chirciu; Daniel Sitaru; Neculai Stanciu; Octavian Stroe
The book contains 400 problems in algebra, number theory, combinatorics, and geometry, from all over the world. It is an excellent text for preparing mathematics competitions of all levels. That is why I strongly recommend this book for mathematics teachers and gifted students.