To cite package 'rusda' in publications use:

  Franz-Sebastian Krah, Hanno Schaeffer, Christoph Heibl, Claus
  B{"{a}}ssler, John Soghigian, David Hibbett (2018) Evolutionary
  dynamics of host specialization in wood-decay fungi BMC Evolutionary
  Biology, 18(1):119-132.

A BibTeX entry for LaTeX users is

  @Article{,
    author = {Franz-Sebastian Krah and Hanno Schaefer and Christoph Heibl and Claus B{"{a}}ssler and John Soghigian and David Hibbett},
    title = {Evolutionary dynamics of host specialization in wood-decay fungi},
    year = {2018},
    journal = {BMC Evolutionary Biology},
    volume = {18},
    issue = {1},
    pages = {119-132},
  }