Cortes, L. P., Basa, E. Y., Estrera, J. A., Galvante, W. P., Rodriguez, V. L., Banta, S. J., & Acacio, R. C. (1983). Earth science: The Philippines in focus. Institute for Science and Mathematics Education Development, University of the Philippines.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रCortes, Leticia P., Erlinda Yolo Basa, Josefina A. Estrera, Wulfilda P. Galvante, Violeta L. Rodriguez, Stephen J. Banta, और Rogelio C. Acacio. Earth Science: The Philippines in Focus. Quezon City: Institute for Science and Mathematics Education Development, University of the Philippines, 1983.
एमएलए (9वां संस्करण) प्रशस्ति पत्रCortes, Leticia P., et al. Earth Science: The Philippines in Focus. Institute for Science and Mathematics Education Development, University of the Philippines, 1983.
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