The book deals with algorithmic problems related to binary quadratic forms. Written by a world leader in number theory, it is the only book focusing on the algorithmic aspects of the theory. It deals with problems such as finding the representations of an integer by a form with integer coefficients, finding the minimum of a form with real coefficients and deciding equivalence of two forms. In order to solve those problems, the book introduces the reader to important areas of number theory such as diophantine equations, reduction theory of quadratic forms, geometry of numbers and algebraic number theory. The book explains applications to cryptography. It requires only basic mathematical knowledge.

Buchmann: Professor of Computer Science and Mathematics
   special areas number theory, computer algebra, cryptography
   associate editor Journal of Cryptology
          Leibniz Award of the Deutsche Forschungsgemeinschaft
   Author of "Introduction to cryptography" UTM, translated into seven languages
          Member of Berlin-Brandenburg Academy of Sciences
          Member of Academy of Sciences and Literature, Mainz

Vollmer: Thesis and several articles on algorithms for Class Group and Regulator computation in quadratic fields.