The major part of the book is quite elementary and is easily accessible to an undergraduate student. The less elementary parts, such as Galois theory or group representations and their characters, would need a more profound knowledge of mathematics. The reader may either take the basic facts of these theories for granted or use our book as a motivation and a first approach to these subjects.
Lomonosov Moscow State University, Moscow, Russia
Ben Gurion University of the Negev, Be’er Sheva, Israel
University of Bordeaux, Talence, France