@misc{indiciaec3961d942b46,
  title = {Some sources of difficulty in solving simple problems.},
  author = {J J GOODNOW and T F PETTIGREW},
  year = {1956},
  doi = {10.1037/h0049059},
  url = {https://pubmed.ncbi.nlm.nih.gov/13319610/},
  note = {Source identifier: 13319610}
}