@misc{indiciae618b6235f9ae,
  title = {What is ... distance learning?},
  author = {R M Harden},
  year = {1988},
  doi = {10.3109/01421598809010534},
  url = {https://pubmed.ncbi.nlm.nih.gov/2465476/},
  note = {Source identifier: 2465476}
}