Gaya APA

LANGBEIN, L, I. (1980). DISCOVERING WHETHER PROGRAMS WORK : A GUIDE TO STATISTICAL METHODSFOR PROGRAM EVALUATION . : LIBRARY OFF CONGRESS CATALOGIING.

Gaya MLA

LANGBEIN, LAURA, IRWIN. "DISCOVERING WHETHER PROGRAMS WORK : A GUIDE TO STATISTICAL METHODSFOR PROGRAM EVALUATION". : LIBRARY OFF CONGRESS CATALOGIING, 1980. Text.