Gutiérrez R., J., C. Aparicio N., and R. M. Larios. “Establíshmerzt of Barpressing Itt Rats Using Electric Sho Ch: Evaluation of Dzfferertt Temporal Relationships”. Mexican Journal of Behavior Analysis, vol. 1, no. 2, Aug. 2011, pp. 107-19, doi:10.5514/rmac.v1.i2.26927.