American Society of Training Directors. (1961). Selected bibliographies covering twenty-seven training subjects. s.n.
Dyfyniad Arddull ChicagoAmerican Society of Training Directors. Selected Bibliographies Covering Twenty-seven Training Subjects. Madison, Wis: s.n, 1961.
Dyfyniad MLAAmerican Society of Training Directors. Selected Bibliographies Covering Twenty-seven Training Subjects. s.n, 1961.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.