To cite rscala in publications use:

Dahl DB (2020). “Integration of R and Scala Using rscala.” Journal of Statistical Software, 92(4), 1–18. doi: 10.18637/jss.v092.i04.

Corresponding BibTeX entry:

  @Article{,
    title = {Integration of {R} and {Scala} Using {rscala}},
    author = {David B. Dahl},
    journal = {Journal of Statistical Software},
    year = {2020},
    volume = {92},
    number = {4},
    pages = {1--18},
    doi = {10.18637/jss.v092.i04},
  }