@misc{indiciaeb59dc2f23b05,
  title = {A Fundamental Theorem in Modifiability.},
  author = {E L Thorndike},
  year = {1927},
  doi = {10.1073/pnas.13.1.15},
  url = {https://pubmed.ncbi.nlm.nih.gov/16577086/},
  note = {Source identifier: 16577086}
}