Aššur-šaddûni, son of Nūr-ili [http://oracc.museum.upenn.edu/riao/fromsamsiaddutomittanicilent18081364bc/mittanianhegemony/nurili/index.html], is said to have ruled over Assyria for only one month (ca. mid-15th century BCE). According to the Assyrian King List [http://oracc.museum.upenn.edu/riao/kinglists/assyriankinglist/assyriankinglist/index.html#Mittani], his uncle Aššur-rabi I [http://oracc.museum.upenn.edu/riao/fromsamsiaddutomittanicilent18081364bc/mittanianhegemony/ashurrabii/index.html] removed him from the throne. Aššur-šaddûni's short reign is mentioned in theSynchronistic King List [http://oracc.museum.upenn.edu/riao/kinglists/synchronistickinglist/index.html#List]. Unfortunately, the name of the contemporary king of Babylon is completely broken away. Due to the brevity of his tenure as king, it comes as no surprise that no inscriptions of Aššur-šaddûni have yet come to light.
Yehonatan Hershkovitz
Yehonatan Hershkovitz, 'Aššur-šaddûni', The Royal Inscriptions of Assyria online (RIAo) Project, The RIAo Project, a sub-project of MOCCI, 2017 [http://oracc.museum.upenn.edu/riao/fromsamsiaddutomittanicilent18081364bc/mittanianhegemony/ashurshadduni/]