Dyfyniad APA
ebrary, Inc. (1989). Opportunities in biology. National Academy Press.
Dyfyniad Arddull Chicago
ebrary, Inc. Opportunities in Biology. Washington: National Academy Press, 1989.
Dyfyniad MLA
ebrary, Inc. Opportunities in Biology. National Academy Press, 1989.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.