"Licence for Richard ,duke of York, to build within the manor of Honesdon, co. Hertford, a tower of stones with lime and sand, and to embattle the same, and to hold the manor and tower to him, his heirs and assigns."
Granted at Westminster, by King etc..
Original source is
(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;
More details about licences to crenellate can be found here.
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