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Kales A, Manfredi RL, Vgontzas AN, Bixler EO, Vela-Bueno A, Fee EC.Kales A, et al. Among authors: vgontzas an.Clin Pharmacol Ther. 1991 Apr;49(4):468-76. doi: 10.1038/clpt.1991.55.Clin Pharmacol Ther. 1991.PMID: 2015735Clinical Trial.