Kevin M. Beaver, John Paul Wright (2011). ”The association between county-level IQ and county-level crime rates”. Intelligence (39): sid. 25. doi:10.1016/j.intell.2010.12.002.
Jared M. Bartels, Joseph J. Ryan, Lynn S. Urban, Laura A. Glass (2010). ”Correlations between estimates of state IQ and FBI crime statistics”. Personality and Individual Differences (48): sid. 579–583. doi:10.1016/j.paid.2009.12.010.