Editors. "The Warden of the East March is captured by the Scots". The Literary Encyclopedia. First published 01 November 2010
[http://www.litencyc.com/php/stopics.php?rec=true&UID=14671, accessed 21 April 2014.]
Sir Robert Bowes, Warden of the East March, is captured by the Scots at Hadden Rigg, while he is undertaking a punitive raid into their territory of Teviotdale.