Tapia, A.K.G., Cammayo, M.O. and Herrera, M.U. 2005. Intrinsic and extrinsic motivations of introductory Physics students. Proceedings of the Samahang Pisika ng Pilipinas, 23(1), SPP-2005-PB-09. URL: https://proceedings.spp-online.org/article/view/SPP-2005-PB-09.