Effects of SKF-83566 and haloperidol on performance on progressive ratio schedules maintained by sucrose and corn oil reinforcement: quantitative analysis using a new model derived from the Mathematical Principles of Reinforcement (MPR) - Olarte-Sánchez, C. M.; Valencia-Torres, L.; Cassaday, H. J.; Bradshaw, C. M.; Szabadi, E. (Psychopharmacology, 2013)