Bhargava, S., K. R. Rajanna, and K. R. Vasuki. “On Some Ramanujan Identities for the Ratios of Eta-Functions”. Ukrains’kyi Matematychnyi Zhurnal, Vol. 66, no. 8, Aug. 2014, pp. 1011–1028, https://umj.imath.kiev.ua/index.php/umj/article/view/2196.