Continua: With the Houston Problem Book
Volume 170 of the series Lecture Notes in Pure and Applied Mathematics
Howard Cook, W. T. Ingram, and K. T. Kuperberg
Marcel Dekker, City of publication unknown: 1995
Paperback. 402 pages. ISBN 0-8247-9650-0
Definitions, Solved and Unsolved Problems, Conjectures, and Theorems in Number Theory and Geometry
Florentin Smarandache
Xiquan Publishing House, City of publication unknown: 2000
Paperback. 84 pages. ISBN 1-879585-74-X
Erdos on Graphs: His legacy of unsolved problems
Fan R. K. Chung and Ronald L. Graham
A K Peters, Wellesley, MA: 1998
Hardcover. 142 pages. ISBN 1-56881-079-2 LCCN 97-046327
Mathématiques de demain, problčmes non résolus
Charles Stanley Ogilvy
Dunod, Paris: 1966
Unknown binding. 152 pages. French. LCCN 72-381436
Old and New Unsolved Problems in Plane Geometry and Number Theory
Volume 11 of the series Dolciani mathematical expositions
Victor Klee and Stan Wagon
Mathematical Association of America, Washington, DC: 1991
Hardcover. 333 pages. ISBN 0-88385-315-9 LCCN 91-061591
Only Problems, Not Solutions!
Florentin Smarandache
Xiquan Publishing House, Phoenix: 1991
Hardcover. 35 pages. ISBN 1-879585-00-6 LCCN 92-108051
Open Problems in Topology
Jan Van Mill, George M. Reed, and J. Van Mill
North-Holland, Amsterdam: 1990
Hardcover. 692 pages. ISBN 0-444-88768-7 LCCN 90-041321
Open questions in mathematics
Various
Bormeol-Oaks Press, City of publication unknown: 1974
Unknown binding. LCCN 75-002316
Proposed Problems of Mathematics
Florentin Smarandache
Universitatea de Stat din Moldova, Catedra de Algebra, Chisinau: 1998
Paperback. 96 pages. ISBN 1-879585-37-5 LCCN 98-151557
Solved and Unsolved Problems in Number Theory
Daniel Shanks
Spartan Books, Washington: 1962
Hardcover. LCCN 62-018192
Solved and Unsolved Problems in Number Theory, 2nd edition
A volume in the series Chelsea Publishing Series
Daniel Shanks
Chelsea, New York: 1978
Unknown binding. 258 pages. ISBN 0-8284-0297-3 LCCN 77-013019
Solved and Unsolved Problems in Number Theory, 3rd edition
A volume in the series Chelsea Publishing Series
Daniel Shanks
Chelsea, New York: 1985
Hardcover. 304 pages. ISBN 0-8284-1297-9 LCCN 85-207520
Solved and Unsolved Problems in Number Theory, 4th edition
A volume in the series Chelsea Publishing Series
Daniel Shanks
Chelsea, New York: 1993
Hardcover. 304 pages. ISBN 0-8284-2297-4
Solved and Unsolved Problems in Number Theory, 5th edition
Volume 297 of the series AMS Chelsea Publishing
Daniel Shanks
American Mathematical Society, Providence, RI: 2002
Hardcover. 304 pages. ISBN 0-8218-2824-X
The Kourovka Notebook: Unsolved problems in group theory
Volume 121 of the series American Mathematical Society translations
L. Ia Leifman, Kourovskaia Tetrad., and D. J. Johnson
American Mathematical Society, Providence, RI: 1983
Hardcover. 112 pages. ISBN 0-8218-3079-1 LCCN 83-009965
The Millennium Problems: The seven greatest unsolved mathematical puzzles of our time
Keith J. Devlin
Basic Books, New York: 2002
Hardcover. 237 pages. ISBN 0-465-01729-0 LCCN 2003-535468
The Scottish book: Mathematics from the Scottish Cafe
Dan Mauldin
Birkhauser, Boston: 1981
Hardcover. 268 pages. ISBN 3-7643-3045-7 LCCN 81-009934
TomorrowŐs Math: Unsolved problems for the amateur
Charles Stanley Ogilvy
Oxford University Press, New York: 1962
Unknown binding. 182 pages. LCCN 62-016577
TomorrowŐs Math: Unsolved problems for the amateur, 2nd edition
Charles Stanley Ogilvy
Oxford University Press, New York: 1972
Hardcover. 198 pages. ISBN 0-19-501508-8 LCCN 77-173328
Ungelöste und unlösbare Probleme der Geometrie
Herbert Meschkowski
Bibliographisches Institut, Mannheim: 1975
Hardcover. 203 pages. German. ISBN 3-411-01483-0 LCCN 76-472114
Unsolved and unsolvable problems in geometry
Herbert Meschkowski
F. Ungar, New York: 1966
Unknown binding. 168 pages. LCCN 65-025028
Unsolved and unsolvable problems in geometry
Herbert Meschkowski
London, Oliver & Boyd, Edinburgh: 1966
Unknown binding. 168 pages. LCCN 66-073572
Unsolved problems
Various
Mathematics Dept. Simon Fraser University, Burnaby, BC: 1980
Unknown binding. LCCN 80-502840
Unsolved Problems Concerning Lattice Points
J. Hammer
Pitman Publishing, London: 1977
Paperback. 101 pages. ISBN 0-273-01103-0 LCCN 78-308420
Unsolved Problems in Geometry
A volume in the series Problem Books in Mathematics
Hallard T. Croft, Kenneth J. Falconer, and Richard K. Guy
Springer-Verlag, New York: 1995
Hardcover. 198 pages. ISBN 0-387-97506-3
Unsolved Problems in Number Theory
Volume 1 of the series Problem Books in Mathematics
Richard K. Guy
Springer-Verlag, New York: 1981
Hardcover. 161 pages. ISBN 0-387-90593-6 LCCN 81-009183
Unsolved Problems in Number theory, 2nd edition
A volume in the series Problem Books in Mathematics
Richard K. Guy
Springer-Verlag, New York: 1994
Hardcover. 285 pages. ISBN 0-387-94289-0 LCCN 94-003818
Unsolved Problems on Mathematics for the 21st Century: A Tribute to Kiyoshi IskiŐs 80th Birthday
J. M. Abe
IOS Press, Amsterdam: 2001
Hardcover. 319 pages. ISBN 9051994907 LCCN 00-111252
Unsolved problems related to Smarandache function
Florentin Smarandache
Number Theory Pub. Co., Phoenix: 1993
Hardcover. 66 pages. ISBN 1-879585-37-5 LCCN 93-220300