00629nam a2200193Ia 450000500170000000800460001703700120006304000210007504100130009608400220010910000320013124500580016325000060022126000500022730000100027794200220028799900210030995201050033020250508161025.0008  250505s9999    xx            000 0 eng d  aTextual  aFEDL bengcFEDL  aeng2eng  a001.42, VANqFEDL  aVan Dalen Deobold B9758718 0aUnderstanding educational research : An introducation  a4  aNew York, USAbMcGraw-Hill Book Companyc1979  a547p.  cTEXLh001.42, VAN  c1367987d1367987  00104070aFEDLbFEDLd2025-05-08l0o001.42, VANpEL0055115r2025-05-08 16:10:25w2025-05-08yTEXL