TY  - GEN
AU  - Pelgrum, Willem
AU  - Plomp, Tjeerd
TI  - Theoretical framework, design and sampling
KW  - Psicologia Educacional
KW  - 3500 - Psicologia Educacional
UR  - https://catalogo.ispa.pt/opac/biblioteca/localizacao_doc/e2.htm
ER  -