Science and Mathematics Education Manpower Development Project (SMEMDP) & Tan, M. C. (1998). Sourcebook on practical work for teacher trainers: High school earth/environmental science (Exp'l ed.). SMEMDP.
Lua i Stíl Chicago (17ú heag.)Science and Mathematics Education Manpower Development Project (SMEMDP) agus Merle C. Tan. Sourcebook on Practical Work for Teacher Trainers: High School Earth/environmental Science. Exp'l ed. Diliman, Quezon City: SMEMDP, 1998.
Lua MLA (9ú heag.)Science and Mathematics Education Manpower Development Project (SMEMDP) agus Merle C. Tan. Sourcebook on Practical Work for Teacher Trainers: High School Earth/environmental Science. Exp'l ed. SMEMDP, 1998.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.