Dyfyniad APA

National Association of Secondary School Principals (U.S.). (1972). NASSP bulletin. National Association of Secondary School Principals].

Dyfyniad Arddull Chicago

National Association of Secondary School Principals (U.S.). NASSP Bulletin. [Reston, Va. [etc.]: National Association of Secondary School Principals], 1972.

Dyfyniad MLA

National Association of Secondary School Principals (U.S.). NASSP Bulletin. National Association of Secondary School Principals], 1972.

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