Dyfyniad APA

OPEN UNIVERSITY. S25-COURSE TEAM. ORBITALS.

Dyfyniad Arddull Chicago

OPEN UNIVERSITY. S25-COURSE TEAM. ORBITALS. 2ND ED. BLETCHLEY, OPEN UNIV. PR., 1973. 55, 56P.

Dyfyniad MLA

OPEN UNIVERSITY. S25-COURSE TEAM. ORBITALS.

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