To cite iNEXT in publications use:

Hsieh TC, Ma KH, Chao A (2020). iNEXT: Interpolation and Extrapolation for Species Diversity. R package version 2.0.20, http://chao.stat.nthu.edu.tw/wordpress/software_download/.

Chao A, Gotelli NJ, Hsieh TC, Sande EL, Ma KH, Colwell RK, Ellison AM (2014). “Rarefaction and extrapolation with Hill numbers: a framework for sampling and estimation in species diversity studies.” Ecological Monographs, 84, 45–67.

Corresponding BibTeX entries:

  @Manual{,
    title = {iNEXT: Interpolation and Extrapolation for Species
      Diversity},
    author = {T. C. Hsieh and K. H. Ma and Anne Chao},
    year = {2020},
    note = {R package version 2.0.20},
    url = {http://chao.stat.nthu.edu.tw/wordpress/software_download/},
  }
  @Article{,
    title = {Rarefaction and extrapolation with Hill numbers: a
      framework for sampling and estimation in species diversity
      studies},
    author = {Anne Chao and Nicholas J. Gotelli and T. C. Hsieh and
      Elizabeth L. Sande and K. H. Ma and Robert K. Colwell and Aaron
      M. Ellison},
    journal = {Ecological Monographs},
    year = {2014},
    volume = {84},
    pages = {45--67},
  }