@misc{indiciaecc6b273cc6ca,
  title = {The Marbles test. A test for small groups.},
  author = {R J Usandivaras and W R Grimson and H Hammond and E Issaharoff and D Romanos},
  year = {1967},
  doi = {10.1001/archpsyc.1967.01730250111016},
  url = {https://pubmed.ncbi.nlm.nih.gov/4952156/},
  note = {Source identifier: 4952156}
}