Cita APA (7th ed.)

Ruskin, R. S. (1974). The personalized system of instruction: An educational alternative. Americam Association for Higher Education.

Cita Chicago (17th ed.)

Ruskin, Robert S. The Personalized System of Instruction: An Educational Alternative. Washington, D.C.: Americam Association for Higher Education, 1974.

Cita MLA (9th ed.)

Ruskin, Robert S. The Personalized System of Instruction: An Educational Alternative. Americam Association for Higher Education, 1974.