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Newman B, O'Grady MA, Ryan CS, Hemmes NS (1993). "Pavlovian conditioning of the tickle response of human subjects: Temporal and delay conditioning". Perceptual and Motor Skills. 77 (3 Pt 1): 779–785. doi:10.2466/pms.1993.77.3.779. PMID8284153. S2CID38446310.
Lahuerta J, et al. (1990). "Clinical and instrumental evaluation of sensory function before and after percutaneous anterolateral cordotomy at cervical level in man". Pain. 42 (1): 23–30. doi:10.1016/0304-3959(90)91087-Y. PMID1700355. S2CID24785416.
Newman B, O'Grady MA, Ryan CS, Hemmes NS (1993). "Pavlovian conditioning of the tickle response of human subjects: Temporal and delay conditioning". Perceptual and Motor Skills. 77 (3 Pt 1): 779–785. doi:10.2466/pms.1993.77.3.779. PMID8284153. S2CID38446310.
Lahuerta J, et al. (1990). "Clinical and instrumental evaluation of sensory function before and after percutaneous anterolateral cordotomy at cervical level in man". Pain. 42 (1): 23–30. doi:10.1016/0304-3959(90)91087-Y. PMID1700355. S2CID24785416.
Newman B, O'Grady MA, Ryan CS, Hemmes NS (1993). "Pavlovian conditioning of the tickle response of human subjects: Temporal and delay conditioning". Perceptual and Motor Skills. 77 (3 Pt 1): 779–785. doi:10.2466/pms.1993.77.3.779. PMID8284153. S2CID38446310.
Loftis, Fridlund; Jennifer (April 1990). "Alan". Relations Between Tickling and Humorous Laughter: Preliminary Support for the Darwin-Hecker Hypothesis. Biological Psychology. 30 (141–150): 201.