To cite tmbstan in publications use:

Monnahan C, Kristensen K (2018). “No-U-turn sampling for fast Bayesian inference in ADMB and TMB: Introducing the adnuts and tmbstan R packages.” PloS one, 13(5). doi: 10.1371/journal.pone.0197954.

Corresponding BibTeX entry:

  @Article{,
    title = {No-U-turn sampling for fast Bayesian inference in ADMB and
      TMB: Introducing the adnuts and tmbstan R packages},
    author = {Cole Monnahan and Kasper Kristensen},
    journal = {PloS one},
    year = {2018},
    volume = {13},
    number = {5},
    doi = {10.1371/journal.pone.0197954},
  }