To cite sns in publications use:

Mahani AS, Hasan A, Jiang M, Sharabiani MTA (2016). “Stochastic Newton Sampler: The R Package sns.” Journal of Statistical Software, Code Snippets, 74(2), 1–33. doi:10.18637/jss.v074.c02.

Corresponding BibTeX entry:

    title = {Stochastic Newton Sampler: The {R} Package {sns}},
    author = {Alireza S. Mahani and Asad Hasan and Marshall Jiang and
      Mansour T. A. Sharabiani},
    journal = {Journal of Statistical Software, Code Snippets},
    year = {2016},
    volume = {74},
    number = {2},
    pages = {1--33},
    doi = {10.18637/jss.v074.c02},