El-Bagary, Ramzia Ismail, Ehab Farouk Elkady, and Bassam Mahfouz Ayoub. 2013. “Simultaneous Determination of Sitagliptin and Metformin in Ternary Mixture With Sitagliptin Acid Degradation Product”. European Journal of Chemistry 4 (4):360-65. https://doi.org/10.5155/eurjchem.4.4.360-365.843.