Roman’kov, V.A. “On the Automorphism Groups of Relatively Free Groups of Infinite Rank: A Survey”. Bulletin of the Karaganda University. Mathematics Series 90, no. 2 (June 30, 2018): 157–162. Accessed August 23, 2025. http://mts.buketov.edu.kz/index.php/mathematics-vestnik/article/view/285.