To cite RSNNS in publications use:

Bergmeir C, Ben\'itez JM (2012). “Neural Networks in R Using the Stuttgart Neural Network Simulator: RSNNS.” Journal of Statistical Software, 46(7), 1–26. https://www.jstatsoft.org/v46/i07/.

Corresponding BibTeX entry:

  @Article{,
    title = {Neural Networks in {R} Using the Stuttgart Neural Network
      Simulator: {RSNNS}},
    author = {Christoph Bergmeir and Jos\'e M. Ben\'itez},
    journal = {Journal of Statistical Software},
    year = {2012},
    volume = {46},
    number = {7},
    pages = {1--26},
    url = {https://www.jstatsoft.org/v46/i07/},
  }