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Ponsonby AL, Williamson E, Smith K, Bridge D, Carmichael A, Jacobs A, Burrill J, Ollington N, Keeffe J, Dwyer T.Ponsonby AL, et al.Ophthalmic Epidemiol. 2009 Sep-Oct;16(5):311-21.Ophthalmic Epidemiol. 2009.PMID: 19874111Clinical Trial.
Ponsonby AL, Smith K, Williamson E, Bridge D, Carmichael A, Dwyer T, Jacobs A, Keeffe J.Ponsonby AL, et al.Optom Vis Sci. 2013 Jan;90(1):75-83. doi: 10.1097/OPX.0b013e3182780dd0.Optom Vis Sci. 2013.PMID: 23241825