To cite package ‘OHPL’ in publications use:

  You-Wu Lin, Nan Xiao, Li-Li Wang, Chuan-Quan Li, and Qing-Song Xu.
  (2017). Ordered homogeneity pursuit lasso for group variable
  selection with applications to spectroscopic data. Chemometrics and
  Intelligent Laboratory Systems 168, 62-71.

A BibTeX entry for LaTeX users is

  @Article{lin2017ordered,
    title = {Ordered homogeneity pursuit lasso for group variable selection with applications to spectroscopic data},
    author = {You-Wu Lin and Nan Xiao and Li-Li Wang and Chuan-Quan Li and Qing-Song Xu},
    journal = {Chemometrics and Intelligent Laboratory Systems},
    volume = {168},
    pages = {62--71},
    year = {2017},
    doi = {10.1016/j.chemolab.2017.07.004},
  }