To cite package ‘OptimalSurrogate’ in publications use:

Wang X, Parast L, Yang M, Tian L, Cai T (2022). OptimalSurrogate: Model Free Approach to Quantifying Surrogacy. R package version 1.0, https://CRAN.R-project.org/package=OptimalSurrogate.

Corresponding BibTeX entry:

  @Manual{,
    title = {OptimalSurrogate: Model Free Approach to Quantifying
      Surrogacy},
    author = {Xuan Wang and Layla Parast and Ming Yang and Lu Tian and
      Tianxi Cai},
    year = {2022},
    note = {R package version 1.0},
    url = {https://CRAN.R-project.org/package=OptimalSurrogate},
  }