Delgado Alvarado, Gustavo. “Validation and Verification of Test Methods. A Dilemma in Testing Laboratories and Accreditation Audits”. Universitas (León) 3, no. 2 (November 4, 2009): 14–21. Accessed December 7, 2025. https://camjol.info/index.php/UNIVERSITAS/article/view/1661.