Valdueza, Johanna Andrea, Jomar Sta Ana, Alleni Junsay, Aaron Dacuya, and Benilda Ebarvia. “Method Development and Validation of Gas Chromatography Methods Using Nitrogen Phosphorus Detector (GC-NPD) and Isotope Dilution Triple Quadrupole Mass Spectrometry (GC-IDMS MS) for the Determination of Chlorpyrifos in Mango”. KIMIKA: The Journal of the Kapisanang Kimika ng Pilipinas 33, no. 1 (March 12, 2022): 1–8. Accessed October 15, 2026. https://kimika.pfcs.org.ph/index.php/kimika/article/view/159.