A mess?
There seems to be a mess about Turners who paint. The page claims that William Turner is sometimes called J. W. M. Turner. The Wikipedia link states that these are two different people, living about the same time and both painting. I cannot help disentangle it as I do not (yet) know the DWU sources. Amorkuz ☎ 23:13, January 28, 2016 (UTC)