@misc{indiciae16ef8ee2ee95,
  title = {Force Density Function Relationships in 2-D Granular Media},
  author = {Youngquist, Robert C. and Metzger, Philip T. and Kilts, Kelly N.},
  year = {2004},
  url = {https://ntrs.nasa.gov/citations/20130011298},
  note = {Source identifier: 20130011298}
}