1. The equalizer conjecture for the free group of rank two;Logan;Q. J. Math.,2021
2. Combinatorial Group Theory;Lyndon,1977
3. The occurrence problem for free products of groups;Mikhaĭlova;Dokl. Akad. Nauk SSSR,1959
4. On Group-Theoretic Decision Problems and Their Classification;Miller,1971
5. A variant of a recursively unsolvable problem;Post;Bull. Am. Math. Soc.,1946