To cite package ‘MatrixModels’ in publications use:

  Bates D, Maechler M (2025). _MatrixModels: Modelling with Sparse and
  Dense Matrices_. R package version 0.6-0, ,
  <https://r-forge.r-project.org/projects/matrix>.

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {MatrixModels: Modelling with Sparse and Dense Matrices},
    author = {Douglas Bates and Martin Maechler},
    year = {2025},
    note = {R package version 0.6-0, 
},
    url = {https://r-forge.r-project.org/projects/matrix},
  }