To cite package ‘lbfgsb3c’ in publications use:

  Fidler ML, Nash JC, Zhu C, Byrd R, Nocedal J, Morales JL (2024).
  _lbfgsb3c: Limited Memory BFGS Minimizer with Bounds on Parameters
  with optim() 'C' Interface_. R package version 2024-3.5, ,
  <https://github.com/nlmixr2/lbfgsb3c>.

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {lbfgsb3c: Limited Memory BFGS Minimizer with Bounds on Parameters with
optim() 'C' Interface},
    author = {Matthew L Fidler and John C Nash and Ciyou Zhu and Richard Byrd and Jorge Nocedal and Jose Luis Morales},
    year = {2024},
    note = {R package version 2024-3.5, 
},
    url = {https://github.com/nlmixr2/lbfgsb3c},
  }