I would imagine we've all been guilty of clicking onto Wikipedia when we Google something, since it is usually one of the first items to appear in search results. However, when I wanted to check something on Albert J. Beveridge, I came across a statement in his biography that made me remember why it's best to take what it says with a block of salt.
Written in the biography is
Beveridge spent most of his final years after his 1922 defeat writing a two volume biography of Abraham Lincoln (two volumes because the work was only half completed), which was published in 1928, the year after his death (he died in Indianapolis, Indiana, aged 64). His accumulated materials for the continuance of the project were handed on to Carl Sandburg at his wife Catherine's request.
It's not footnoted. Looking in Niven's biography of Sandburg there is no mention of it and Beveridge's biographer doesn't mention it either. Beveridge actually saw Sandburg as a rival and expressed his disappointment in Sandburg's work to his correspondents. Also, looking at the
search engine for Sandburg letters in the University of Illinois, it only shows a telegram which Beveridge sent to Sandburg (calling him Karl) and an angry letter Sandburg wrote to Beveridge, which Sandburg never sent.
While I'm not saying this is impossible, this is a good reason not to rely on Wikipedia as a final source.
Best
Rob