00358nam a2200121Ia 450000500170000000800410001708200160005810000200007424500710009426000320016530000150019765000240021220240821155126.0240821s9999||||xx |||||||||||||| ||und||  a001.434 COO  aCook, Thomas D. 0aQuasi-experimentation: design & analysis issues for field settings  aChicagobRand McNallyc1979  axii, 405p.  aExperimental design