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Cas Walker portrait
I believe you misread the note at the bottom of the Knoxville mayors' site. It states that individuals with an asterisk by their name don't have official portraits, and that the portraits shown were taken from the 1891 directory. Walker's name doesn't have an asterisk, and, of course, he wasn't even alive in 1891. Bms4880 (talk) 19:00, 10 July 2012 (UTC)