In 1337 Oct 2, Abbas et Conventus de Buckelond (the abbot and convent) was granted, by Edward III, (In year 11 of his reign) a Royal licence to crenellate Buckelond [Buklond] (Buckland Abbey)

"Licence for the abbot and convent of Buklond to crenellate the dwelling-place and church of their abbey (mansum Abbathiae suae) in the county of Devon."

Granted at Westminster, by privy seal.

Original source is

• Calendar of Patent Rolls (1334-38) p529

(In fact, the original source given is usually a transcription/translation of what are precious medieval documents not readily availably. It should be noted that these transcription/translations often date to the nineteenth or early twentieth centuries and that unwitting bias of transcribers may affect the translation. Care should also be taken to avoid giving modern meaning to the medieval use of certain stock words and terms.)

Significant later source are;

• Higham, R. A., 1988, 'Devon Castles: an annotated list' Proceedings of the Devon Archaeological Society Vol46 p146
  Coulson, C., 1982, 'Hierarchism in Conventual Crenellation' Medieval Archaeology Vol26 p94
  Turner, T.H. and Parker, J.H., 1859, Some account of Domestic Architecture in England (Oxford) Vol3 pt2 p412

More details about licences to crenellate can be found here.

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