Panopio, R. G. (1999). Personalized system of instruction (PSI) for college algebra. Learning Resource Center,University of the Philippines.
Chicago Style aipamenaPanopio, Rolando G. Personalized System of Instruction (PSI) for College Algebra. Diliman, Quezon City: Learning Resource Center,University of the Philippines, 1999.
MLA aipamenaPanopio, Rolando G. Personalized System of Instruction (PSI) for College Algebra. Learning Resource Center,University of the Philippines, 1999.
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