To cite package ‘proxysnps’ in publications use:

  Slowikowski K (2018). _proxysnps: Get proxy SNPs for a SNP in the
  1000 Genomes Project_. R package version 0.0.1,
  <https://github.com/slowkow/proxysnps>.

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {proxysnps: Get proxy SNPs for a SNP in the 1000 Genomes Project},
    author = {Kamil Slowikowski},
    year = {2018},
    note = {R package version 0.0.1},
    url = {https://github.com/slowkow/proxysnps},
  }