C. Xiong, K. Yu, F. Gao, Y. Yan, и Z. Zhang. Clinical trials (London, England), 2 (5):
387-93(января 2005)4845<m:linebreak></m:linebreak>LR: 20071115; GR: AG 03991/AG/NIA NIH HHS/United States; GR: AG 05681/AG/NIA NIH HHS/United States; JID: 101197451; ppublish;<m:linebreak></m:linebreak>Sample size; Comparacions múltiples.