Schechter, Eric, Handbook of Analysis and its Foundations, Academic Press, ISBN 0-126-22760-8.
Lynn Arthur Steen and J. Arthur Seebach, Jr., Counterexamples in Topology, Springer-Verlag, New York, 1978. Reprinted by Dover Publications, New York, 1995. ISBN 0-486-68735-X (Dover edition).
James Munkres(2000), Topology: A frist course, 2nd edition, Prentice-Hall, New Jersey.