Hi Mo,
My recommendation isn’t a book but a useful paper:
Brignell, A., Krahe, M., Downes, M., Kefalianos, E., Reilly, S. & Morgan, A. (2021). Interventions for children and adolescents who stutter: A systematic review, meta-analysis, and evidence map. Journal of Fluency Disorders, 70. https://doi.org/10.1016/j.jfludis.2021.105843.
Isabel