To cite package ‘fieldopt’ in publications use:

  Leite A, Ospina R, Ferraz C (2026). _fieldopt: Area-Frame and
  Dual-Frame Survey Design under Real Field Cost_. R package version
  0.1.0.9001, <https://github.com/castlaboratory/fieldopt>.

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {fieldopt: Area-Frame and Dual-Frame Survey Design under Real Field Cost},
    author = {André Leite and Raydonal Ospina and Cristiano Ferraz},
    year = {2026},
    note = {R package version 0.1.0.9001},
    url = {https://github.com/castlaboratory/fieldopt},
  }