Dyfyniad APA
ebrary, Inc. (1991). The U.S. National Plant Germplasm System. National Academy Press.
Dyfyniad Arddull Chicago
ebrary, Inc. The U.S. National Plant Germplasm System. Washington, D.C.: National Academy Press, 1991.
Dyfyniad MLA
ebrary, Inc. The U.S. National Plant Germplasm System. National Academy Press, 1991.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.