To cite package ‘crsnls’ in publications use:

Tvrdík J (2016). crsnls: Nonlinear Regression Parameters Estimation by 'CRS4HC' and 'CRS4HCe'. R package version 0.2, https://CRAN.R-project.org/package=crsnls.

Corresponding BibTeX entry:

  @Manual{,
    title = {crsnls: Nonlinear Regression Parameters Estimation by
      'CRS4HC' and 'CRS4HCe'},
    author = {Josef Tvrdík},
    year = {2016},
    note = {R package version 0.2},
    url = {https://CRAN.R-project.org/package=crsnls},
  }