@misc{indiciae227b91f0113a,
  title = {HOW MANY LADDERS?},
  author = {D MATTINGLY and P M DENNIS and J PEARSON and C L COPE},
  year = {1964},
  url = {https://pubmed.ncbi.nlm.nih.gov/14206020/},
  note = {Source identifier: 14206020}
}