Agents
Brían mac Con Catha
See also references for related subjects.
Howlett, David, “Rubisca: an edition, translation and commentary”, Peritia 10 (1996): 71–90. 
abstract:
From indications of original internal orthography in two MSS from Saint Augustine’s in Canterbury the editor attempts to restore the authorial text of Rubisca, a brilliant and light-hearted poem in a rare metre, signed by its author, identified here as Brían mac Con Catha, an Irish monk with some knowledge of Hebrew and Greek. Quotations from and allusions to earlier Hiberno-Latin and Anglo-Latin texts suggest composition after the beginning of the ninth century. Diction from this text in an Anglo-Latin and Old English glossary and a charter dated 16 April 928 suggest that the poem, if not the poet, like bishop Dub Innse of Bangor and Israel the Grammarian, may have been known at the court of king Æthelstan.