@misc{indiciaec7bd9f71e2f6,
  title = {On a yield surface for granular materials.},
  author = {Aguirre-Ramirez, G. and Costes, N. C.},
  year = {1972},
  url = {https://ntrs.nasa.gov/citations/19730028530},
  note = {Source identifier: 19730028530}
}