From the reviews: "...a fine book [...] When it appeared in 1949 it was a pioneer. Now there are plenty of competing accounts. But Hasse has something extra to offer.[...] Hasse proved that miracles do happen in his five beautiful papers on quadratic forms of 1923-1924. [...]It is trite but true: Every number-theorist should have this book on his or her shelf." --Irving Kaplansky in Bulletin of the American Mathematical Society, 1981