On the macaronic "Deus meus adiuva me":

In the Coisir Cheoil booklet I have (No. 7), Sean Og says, in rough translation:
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Composed by a Derry poet, Maeliosa O Brolchain, who died in 1086. There is a copy in the Book of Lismore and in the Murphy Manuscript in Maynooth College.

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"Composed" probably refers to the words, in this instance.

Regards