Παραπομπή σε μορφή APA (7η εκδ.)

Nagel, T. S., & Richman, P. T. (1972). Competency-based instruction: A strategy to eliminate failure; a branching programmed text. C.E. Merrill Pub.

Παραπομπή σε μορφή Chicago (17η εκδ.)

Nagel, Thomas S., και Paul T. Richman. Competency-based Instruction: A Strategy to Eliminate Failure; a Branching Programmed Text. Columbus, Ohio: C.E. Merrill Pub, 1972.

Παραπομπή σε μορφή MLA (9th εκδ.)

Nagel, Thomas S., και Paul T. Richman. Competency-based Instruction: A Strategy to Eliminate Failure; a Branching Programmed Text. C.E. Merrill Pub, 1972.