To cite the biomaRt package in publications use:

  Durinck S, Spellman P, Birney E, Huber W (2009). “Mapping identifiers
  for the integration of genomic datasets with the R/Bioconductor
  package biomaRt.” _Nature Protocols_, *4*, 1184-1191.
  doi:10.1038/nprot.2009.97 <https://doi.org/10.1038/nprot.2009.97>.

A BibTeX entry for LaTeX users is

  @Article{,
    title = {Mapping identifiers for the integration of genomic datasets with the R/Bioconductor package biomaRt},
    author = {Steffen Durinck and Paul T. Spellman and Ewan Birney and Wolfgang Huber},
    journal = {Nature Protocols},
    year = {2009},
    volume = {4},
    pages = {1184--1191},
    doi = {10.1038/nprot.2009.97},
  }

  Durinck S, Moreau Y, Kasprzyk A, Davis S, De Moor B, Brazma A, Huber
  W (2005). “BioMart and Bioconductor: a powerful link between
  biological databases and microarray data analysis.” _Bioinformatics_,
  *21*, 3439-3440. doi:10.1093/bioinformatics/bti525
  <https://doi.org/10.1093/bioinformatics/bti525>.

A BibTeX entry for LaTeX users is

  @Article{,
    title = {BioMart and Bioconductor: a powerful link between biological databases and microarray data analysis},
    author = {Steffen Durinck and Yves Moreau and Arek Kasprzyk and Sean Davis and Bart {De Moor} and Alvis Brazma and Wolfgang Huber},
    journal = {Bioinformatics},
    year = {2005},
    volume = {21},
    pages = {3439--3440},
    doi = {10.1093/bioinformatics/bti525},
  }