Campbell Stanley 1959 Exptl Quasi Exptl Designs For Research

EXPERIMENTAL AND QUASI-EXPERIMENTAl DESIGNS FOR RESEARCH DONALD T. CAMPBELL Syracuse University JULIAN C. STANLEY Johns Hopkins University HOUGHTON MIFFLIN COMPANY BOSTON Dallas Geneva, III. Hopewell, N.J. Palo Alto London

EXPERIMENTAL AND QUASI-EXPERIMENTAl DESIGNS FOR RESEARCH DONALD T. CAMPBELL Syracuse University JULIAN C. STANLEY Johns Hopkins University HOUGHTON MIFFLIN COMPANY BOSTON Dallas Geneva, III. Hopewell, N.J. Palo Alto London Less