Corpus of Electronic Texts Edition
The Wooing of Emer by Cú Chulainn (Author: [unknown])

paragraph 38

‘The Back of the Great Sow I said, that is Druimm n-Ebreg. For the shape of a sow appeared to the sons of Milid on every hill and on every height in Erinn, when they came over and wanted to land in it by force, after a spell had been cast on it by the Tuatha De Danann.’