@misc{indiciae56ce96a260b1,
  title = {Keeping the elderly active. Lecture 18.},
  author = {M E Knapp},
  year = {1968},
  doi = {10.1080/00325481.1968.11693359},
  url = {https://pubmed.ncbi.nlm.nih.gov/5663226/},
  note = {Source identifier: 5663226}
}