The original paper:

Zhu R, Zeng D, Kosorok MR (2015). “Reinforcement Learning Trees.” Journal of the American Statistical Association, 110(512), 1770–1784. doi:10.1080/01621459.2015.1036994.

Corresponding BibTeX entry:

  @Article{,
    title = {Reinforcement Learning Trees},
    author = {Ruoqing Zhu and Donglin Zeng and Michael R. Kosorok},
    journal = {Journal of the American Statistical Association},
    year = {2015},
    volume = {110},
    number = {512},
    pages = {1770--1784},
    doi = {10.1080/01621459.2015.1036994},
  }