Encyclopedia Britannica, Volume 4. The Encylopedia Britannica Inc. Gwinn, Norton Chicago. 1987

Living Fishes of The New World
Earl S. Herald
DoubleDay & Company Inc. 1961
Garden Ciy, New York

Encyclopedia Americana (Internation Edition)
Grolier Incorporated 1989

Fishes An Introduction to Icthyology
Peter Moyle.   Prentice Hall Inc.
Englewood Cliffs, New Jersey 1982

Internet Sources:

Tom and Pat Bridges Anableps page:
http://www3.sympatico.ca/tp.bridges/anableps2.html

www.science-frontiers.com/sf004/sf004p05.htm

http://www.cfkc.demon.co.uk/news/vivipaov.htm

http://www.umich.edu/~bio440/fishcapsules98/Anableps.html