That inclusion is not attested in Akkadian versions of the story, nor in contemporary sources, that would date from the period of the Akkadian Empire, but some scholars hold that Hittite version (from  1400 BCE) is conditionally reliable, and probably derived from some local sources.
He is mentioned in only one source, a Hittite version (from  1400 BCE) of an older Akkadian story, that narrates several events related to much earlier times, taking place during the rule of great king Naram-Sin of Akkad (23rd century BCE).