To cite mase in publications use:

Kelly McConville, Josh Yamamoto Becky Tang, George Zhu, Shirley Cheung, and Sida Li (2018). mase: Model-Assisted Survey Estimation. R package version 0.1.4 https://cran.r-project.org/package=mase

Corresponding BibTeX entry:

  @Manual{,
    title = {mase: Model-Assisted Survey Estimation},
    author = {Kelly McConville and Josh Yamamoto and Becky Tang and
      George Zhu and Shirley Cheung and Sida Li},
    year = {2018},
    url = {https://cran.r-project.org/package=mase},
  }