@misc{indiciaec2af2dfd4439,
  title = {Tracing selection effects in three non-probability samples.},
  author = {Cas Barendregt and Agnes van der Poel and Dike van de Mheen},
  year = {2005},
  doi = {10.1159/000085547},
  url = {https://pubmed.ncbi.nlm.nih.gov/15990429/},
  note = {Source identifier: 15990429}
}