Guy, Richard K.
Unsolved problems in number theory - [3rd ed.]. - New York Springer c2004. - xviii, 437 p. - Problem books in mathematics .
0387208607 (acid-free paper)
Number theory.
511 GUY
Unsolved problems in number theory - [3rd ed.]. - New York Springer c2004. - xviii, 437 p. - Problem books in mathematics .
0387208607 (acid-free paper)
Number theory.
511 GUY