To cite package ‘ribd’ in publications use:

  Vigeland MD (2020). “Relatedness coefficients in pedigrees with
  inbred founders.” _Journal of Mathematical Biology_, *81*, 185-207.
  doi:10.1007/s00285-020-01505-x
  <https://doi.org/10.1007/s00285-020-01505-x>.

A BibTeX entry for LaTeX users is

  @Article{,
    author = {Magnus Dehli Vigeland},
    journal = {Journal of Mathematical Biology},
    title = {Relatedness coefficients in pedigrees with inbred founders},
    year = {2020},
    pages = {185--207},
    volume = {81},
    doi = {10.1007/s00285-020-01505-x},
  }

  Vigeland MD (2021). _Pedigree Analysis in R_. Academic Press. ISBN
  978-0128244302.

A BibTeX entry for LaTeX users is

  @Book{,
    title = {Pedigree Analysis in {R}},
    author = {Magnus Dehli Vigeland},
    year = {2021},
    publisher = {Academic Press},
    isbn = {978-0128244302},
  }