Zentall, T. R., & Singer, R. A. Within-trial contrast : Pigeons prefer conditioned reinforcers that follow a relatively more rather than a less aversive event: Perspective on Behavior.

Zentall, Thomas R., و Rebecca A. Singer. Within-trial Contrast : Pigeons Prefer Conditioned Reinforcers That Follow a Relatively More Rather Than a Less Aversive Event: Perspective On Behavior.

Zentall, Thomas R., و Rebecca A. Singer. Within-trial Contrast : Pigeons Prefer Conditioned Reinforcers That Follow a Relatively More Rather Than a Less Aversive Event: Perspective On Behavior.