To cite package ‘Rsolnp’ in publications use:

  Galanos A, Ye Y (2025). _Rsolnp: General Non-Linear Optimization_. R
  package version 2.0.1, <https://CRAN.R-project.org/package=Rsolnp>.

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {Rsolnp: General Non-Linear Optimization},
    author = {Alexios Galanos and Yinyu Ye},
    year = {2025},
    note = {R package version 2.0.1},
    url = {https://CRAN.R-project.org/package=Rsolnp},
  }