A variety of works have been associated with Cormac, such as the "Sanas Cormaic", a glossary of difficult words in Irish in the style of Isidore of Seville, which bears his name. While the core of the document dates from around Cormac's time, and may in some way be linked to him, it is uncertain if he was the compiler of even the original list. The lost "Psalter of Cashel" and the "Lebor na Cert"—the Book of Rights—is also linked to Cormac. The works that survive today are probably from the time of Muirchertach Ua Briain. Liam Breatnach also attributes Amra Senáin to Cormac.