Syrova, G., T. Zvyagintseva, I. Chekman, and T. Nebesna. “Quantopharmacological Substantiation of Potentiate Analgetics Properties of Coffeine”. Farmatsevtychnyi Zhurnal, no. 6, Dec. 2008, pp. 85-91, https://pharmj.org.ua/index.php/journal/article/view/1081.