To cite package 'virustotal' in publications use:

Gaurav Sood (2017). virustotal: R Client for the virustotal API. R package version 0.2.1.

Corresponding BibTeX entry:

  @Manual{,
    title = {virustotal: R Client for the virustotal API},
    author = {Gaurav Sood},
    year = {2017},
    note = {R package version 0.2.1},
  }