To cite LARF in publications use:

  An, Weihua and Xuefu Wang. 2016. LARF: Instrumental Variable
  Estimation of Causal Effects through Local Average Response
  Functions. Journal of Statistical Software 71(1): 1-13.

A BibTeX entry for LaTeX users is

  @Article{,
    title = {{LARF}: Instrumental Variable Estimation of Causal Effects through Local Average Response Functions},
    author = {Weihua An and Xuefu Wang},
    journal = {Journal of Statistical Software},
    year = {2016},
    volume = {71},
    number = {1},
    pages = {1-13},
  }