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Martens MG, Faro S, Hammill HA, Smith D, Riddle G, Maccato M.Martens MG, et al. Among authors: hammill ha.South Med J. 1990 Apr;83(4):408-13. doi: 10.1097/00007611-199004000-00012.South Med J. 1990.PMID: 2181689Clinical Trial.