National Development Group for Educational Innovation & Sumagaysay, L. S. (1980). In-service education for primary teachers: Design formulation. National Development Group for Educational Innovation.
Cita Chicago (17th ed.)National Development Group for Educational Innovation i Lourdes S. Sumagaysay. In-service Education for Primary Teachers: Design Formulation. Manila: National Development Group for Educational Innovation, 1980.
Cita MLA (9th ed.)National Development Group for Educational Innovation i Lourdes S. Sumagaysay. In-service Education for Primary Teachers: Design Formulation. National Development Group for Educational Innovation, 1980.
Atenció: Aquestes cites poden no estar 100% correctes.