When using pwt in publications, please cite both the pwt package and the Penn World Table itself:

To cite pwt, the R package, please use:

Zeileis A, Yang G (2013). pwt: Penn World Table. R package version 7.1-1, http://CRAN.R-project.org/package=pwt.

To cite the Penn World Table (version 7.1), please use:

Heston A, Summers R, Aten B (2012). Penn World Table Version 7.1. Center for International Comparisons of Production, Income and Prices at the University of Pennsylvania. http://pwt.econ.upenn.edu/.

Corresponding BibTeX entries:

  @Manual{,
    title = {pwt: Penn World Table},
    author = {Achim Zeileis and Guan Yang},
    year = {2013},
    note = {R package version 7.1-1},
    url = {http://CRAN.R-project.org/package=pwt},
  }

  @Manual{,
    title = {Penn World Table Version 7.1},
    author = {Alan Heston and Robert Summers and Bettina Aten},
    year = {2012},
    month = {July},
    organization = {Center for International Comparisons of Production,
      Income and Prices at the University of Pennsylvania},
    url = {http://pwt.econ.upenn.edu/},
  }