If you use varSelRF please cite Diaz-Uriarte, 2007 at a minimum. If you refer to the variable selection procedure, you also want to cite Diaz-Uriarte and Alvarez de Andres, 2006.

Diaz-Uriarte R (2007). “GeneSrF and varSelRF: a web-based tool and R package for gene selection and classification using random forest.” BMC Bioinformatics, 8. doi:10.1186/1471-2105-8-328, https://bmcbioinformatics.biomedcentral.com/articles/10.1186/1471-2105-8-328.

Diaz-Uriarte R, de Andres AA (2006). “Gene selection and classification of microarray data using random forest.” BMC Bioinformatics, 7. doi:10.1186/1471-2105-7-3, https://bmcbioinformatics.biomedcentral.com/articles/10.1186/1471-2105-7-3.

Corresponding BibTeX entries:

  @Article{,
    author = {R Diaz-Uriarte},
    title = {GeneSrF and varSelRF: a web-based tool and R package for
      gene selection and classification using random forest},
    journal = {BMC Bioinformatics},
    year = {2007},
    doi = {10.1186/1471-2105-8-328},
    url =
      {https://bmcbioinformatics.biomedcentral.com/articles/10.1186/1471-2105-8-328},
    volume = {8},
  }

  @Article{,
    author = {R Diaz-Uriarte and A Alvarez {de Andres}},
    title = {Gene selection and classification of microarray data using
      random forest.},
    journal = {BMC Bioinformatics},
    year = {2006},
    doi = {10.1186/1471-2105-7-3},
    url =
      {https://bmcbioinformatics.biomedcentral.com/articles/10.1186/1471-2105-7-3},
    volume = {7},
  }