@Article{SCI:Bur2012a,
  author =    "J.A. Burghardt and R.M. Brannon",
  title =     "A Nonlocal Plasticity Formulation for the Material
              Point Method",
  journal =   "Computer Methods in Applied Mechanics and
              Engineering",
  volume =    "225--228",
  pages =     "55--64",
  year =      "2012",
  url =       "http://www.sci.utah.edu/publications/Bur2012a/Burghardt_CMAME2012.pdf",
}