Hardnaulee, D. M., and V. S. Bhikkhu. “The Concept of Passionless Mind (Virāga Citta) in Theravāda Buddhism”. The Journal of International Buddhist Studies College (JIBSC), vol. 6, no. 1, Jan. 2021, pp. 38-60, https://so03.tci-thaijo.org/index.php/ibsc/article/view/234193.