Determining the freshness of Oreochromis niloticus niloticus (Tilapia) by NNIR spectroscopy - Agum, Jannah Melody Grace R.; Bernardo, Kriselle Ann D. C.; Carreon, Paul Jerome M.; Galicia, G. F.; Intal, Jonathan Q.; Rongavilla, Kenneth Rodson P.; Subida, Angelique N. (Proceedings of the 25th Samahang Pisika ng Pilipinas Physics Congress, 2007)