National Development Group for Educational Innovation & Sumagaysay, L. S. (1980). In-service education for primary teachers: Design formulation. National Development Group for Educational Innovation.
Chicago-referens (17:e uppl.)National Development Group for Educational Innovation och Lourdes S. Sumagaysay. In-service Education for Primary Teachers: Design Formulation. Manila: National Development Group for Educational Innovation, 1980.
MLA-referens (9:e uppl.)National Development Group for Educational Innovation och Lourdes S. Sumagaysay. In-service Education for Primary Teachers: Design Formulation. National Development Group for Educational Innovation, 1980.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.