Dictionnaire Infernal - Collin de Plancy (1863)
Cerbere/ Cerberus/ Naberus is a strong and powerful demon commanding 29 legions. One of the marquis of hell. Cerberus appears as a three headed dog or a raven. He has a raucous voice but presents himself as eloquent and amiable. He teaches the art of gracious living.
Fallen angel who appears as a crowing c**k (rooster).
Pseudomonarchia daemonum - Johann Wier (1583)
Naberius [Naberus], alias Cerberus, is a valiant marquesse, shewing himselfe in the forme of a crowe, when he speaketh with a hoarse voice: he maketh a man amiable and cunning in all arts, and speciallie in rhetorike, he procureth the losse of prelacies and dignities: nineteene legions heare (and obeie) him.
Goetia - S. L. MacGregor Mathers (1904)
The Twenty-fourth Spirit is Naberius. He is a most valiant Marquis, and showeth in the form of a Black Crane, fluttering about the Circle, and when he speaketh it is with a hoarse voice. He maketh men cunning in all Arts and Sciences, but especially in the Art of Rhetoric. He restoreth lost Dignities and Honours. He governeth 19 Legions of Spirits.