Παραπομπή σε μορφή APA (7η εκδ.)

Langbein, L. I. (1980). Discovering whether programs work: A guide to statistical methods for program evaluation. Scott, Foresman.

Παραπομπή σε μορφή Chicago (17η εκδ.)

Langbein, Laura Irwin. Discovering Whether Programs Work: A Guide to Statistical Methods for Program Evaluation. Glenview, Ill: Scott, Foresman, 1980.

Παραπομπή σε μορφή MLA (9th εκδ.)

Langbein, Laura Irwin. Discovering Whether Programs Work: A Guide to Statistical Methods for Program Evaluation. Scott, Foresman, 1980.