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Hollowell JG, van Assendelft OW, Gunter EW, Lewis BG, Najjar M, Pfeiffer C; Centers for Disease Control and Prevention, National Center for Health Statistics.Hollowell JG, et al.Vital Health Stat 11. 2005 Mar;(247):1-156.Vital Health Stat 11. 2005.PMID: 15782774Free article.