@misc{indiciae6dc48a6c2016,
  title = {Optimality criteria in structural design.},
  author = {W Prager},
  year = {1968},
  doi = {10.1073/pnas.61.3.794},
  url = {https://pubmed.ncbi.nlm.nih.gov/16591709/},
  note = {Source identifier: 16591709}
}