Fleming A, Olson JA, Sharp PF, Goatman KA, Philip S. Response to 'Improved automated screening of diabetic retinopathy' by Carlos M. Oliveira et al. Ophthalmologica. 2012 Jan 1;227(3):173. doi: 10.1159/000334922
Derby CA, Araujo AB, Johannes CB, Feldman HA, McKinlay JB. Measurement of erectile dysfunction in population-based studies: the use of a single question self-assessment in the Massachusetts Male Aging Study. Int J Impot Res. 2000 Aug 1;12(4):197-204.