00373nam a2200133Ia 4500008004100000082001600041100002500057245004400082250001200126260003800138300001400176600002400190650002500214140224s9999    xx            000 0 und d  a37.001.5 K9  aTravers, Robert M.W.  aAn introduction to educational research  a3rd ed.  aLondonbCollice-Macmillancc 1969  axxi,450p.  aRobert M.W. Travers  aEducational research