On this index
and in the corresponding TEI file
I changed "Anonymous" to "Kent, William Charles Mark," as the author of the review, "Walt Whitman's Poems." The London Sun (17 April 1868): 31490.
Edward Dowden in his Walt Whitman and his English Critics claims that his friend Charles Kent [William Charles Mark Kent, 1823-1902] wrote this review, and that William Michael Rossetti confirmed this information.