Mustafa Gülfen, and Yazgı Canbaz , trans. 2020. “Ratio - First Order Derivative - Zero Crossing UV-Visible Spectrophotometric Method for Analysis of Amoxicillin, Levofloxacin and Lansoprazole Mixture”. Pakistan Journal of Analytical & Environmental Chemistry 21 (1): 34 – 43. https://doi.org/10.21743/pjaec/2020.06.05.