Editors. "The Earl of Morton discovers the Casket Letters". The Literary Encyclopedia. First published 01 February 2011
[http://www.litencyc.com/php/stopics.php?rec=true&UID=15062, accessed 22 May 2013.]
The Earl of Morton discovers the Casket Letters. This correspondence, between Mary Queen of Scots and the Earl of Bothwell, potentially implicated Mary in the murder of her second husband Lord Darnley, but their authenticity is a long-standing point of contention.