The Verse Account of Nabonidus
A Babylonian poem written after the Persian conquest that attacks Nabonidus and praises Cyrus. It says that Nabonidus handed the army and the kingship to his eldest son and went away to Tayma.
See the object at britishmuseum.org ↗English translation (Livius) ↗
The tablet is a piece of polemic composed in Babylon under Persian rule. It accuses Nabonidus of neglecting Marduk for the moon god, of stopping the New Year festival and of leaving the country for Tayma in Arabia, and it contrasts him with the pious Cyrus the Great.
For all its bias it is close to the events. Its statement that Nabonidus “entrusted the kingship” to his first-born son when he left for Tayma is the nearest that any Babylonian text comes to the title that the book of Daniel gives to Belshazzar.