@misc{indiciae0393611c7a95,
  title = {Some electronic control units for operant behavior studies. II. A random ratio generator.},
  author = {W N SCHOENFELD and W W CUMMING and A G SNAPPER and P HAAS},
  year = {1960},
  doi = {10.1901/jeab.1960.3-107},
  url = {https://pubmed.ncbi.nlm.nih.gov/14443383/},
  note = {Source identifier: 14443383}
}