1067–70. PMID 2117046. doi:10.1111/j.1471-4159.1990.tb04599.x. Schultz W. Predictive reward signal of dopamine neurons. J. Neurophysiol. 1998, 80 (1): 1–27
Magnus Hofrenning; Moum, Bjørn A; Høivik, Marte Lie; Hovde, Øistein. Predictive factors for a severe clinical course in ulcerative colitis: Results from