Michael D. Zeiler, «Fixed-Interval Behavior: Effects of Percentage Reinforcement», Journal of the Experimental Analysis of Behavior 17, no. 2 (март 1972): 177–89. См. также also, Michael D. Zeiler, «Fixed and Variable Schedules of Response-Independent Reinforcement», Journal of the Experimental Analysis of Behavior 11, no. 4 (июль 1968): 405–14.
