Knapp, R K Acquisition and extinction of avoidance with similar and different shock and escape situations. [electronic resource] - Journal of comparative and physiological psychology Oct 1965 - 272-3 p. digital Publication Type: Journal Article ISSN: 0021-9940 Standard No.: 10.1037/h0022354 doi Subjects--Topical Terms: AnimalsAvoidance LearningConditioning, PsychologicalElectroshockExtinction, PsychologicalRats