Magnus request was very good but here an other one : the 100 author with the most page on Wikisource.

http://tinyurl.com/mut5gzn

Caveat, there is still a lot of work to do on Wikidata, some pages are probably missing (I can help there if needed) and the real numbers are higher than this request show.
(and sorry, the label service label didn't work "time out")

The top 10 is :
id name number
wd:Q16867 Edgar Allan Poe 28
wd:Q9061 Marx 27
wd:Q692 Shakespeare 25
wd:Q34787 Engels 24
wd:Q7243 Tolstoï 23
wd:Q22670 Schiller 21
wd:Q7200 Pushkin 21
wd:Q5879 Goethe 20
wd:Q6197 Horace 20
wd:Q501 Baudelaire 20
(not exactly what I foresee before, the UN texts and the Bible has no unique author, it's logical it doesn't show here ; I forgot the russian author, mea magna culpa! and in fine, I'm surprised and sad not to see Doyle, Dickens, Stevenson, Verne here... at least, they are not far behind and they made it to the top 100 ;) )

Cdlt, ~nicolas