To cite spfda in publications use:

Wang Z, Magnotti JF, Beauchamp MS, Li M (2020). “Functional Group Bridge for Simultaneous Regression and Support Estimation.” arXiv.

Corresponding BibTeX entry:

  @Article{,
    title = {Functional Group Bridge for Simultaneous Regression and
      Support Estimation},
    author = {Zhengjia Wang and John F. Magnotti and Michael S.
      Beauchamp and Meng Li},
    journal = {arXiv},
    year = {2020},
  }