M. Rizk, A. K. Attia, H. Y. Mohamed, and M. Elshahed, “Stability indicating HPLC-Fluorescence detection method for the simultaneous determination of linagliptin and empagliflozin in their combined pharmaceutical preparation”, Eur. J. Chem., vol. 12, no. 2, pp. 168–178, Jun. 2021.