Dyfyniad APA

National Research Council (U.S.). Space Studies Board, National Academy Press (U.S.), & ebrary, Inc. (1999). Annual report. National Academy Press.

Dyfyniad Arddull Chicago

National Research Council (U.S.). Space Studies Board, National Academy Press (U.S.), and Inc ebrary. Annual Report. Washington, D.C.: National Academy Press, 1999.

Dyfyniad MLA

National Research Council (U.S.). Space Studies Board, et al. Annual Report. National Academy Press, 1999.

Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.