Baumslag, Gilbert; Fine, Benjamin; Rosenberger, Gerhard (2019). "One-relator groups: an overview". Groups St Andrews 2017 in Birmingham. London Math. Soc. Lecture Note Ser. Vol. 455. Cambridge University Press. pp. 119–157. ISBN978-1-108-72874-4. MR3931411.
Baumslag, Gilbert; Fine, Benjamin; Rosenberger, Gerhard (2019). "One-relator groups: an overview". Groups St Andrews 2017 in Birmingham. London Math. Soc. Lecture Note Ser. Vol. 455. Cambridge University Press. pp. 119–157. ISBN978-1-108-72874-4. MR3931411.