Amenemhat II
Amenemhat II and his successor Senusret II shared a brief coregency, the only unquestionable one of the whole Middle Kingdom. Unlike most of the double-dated monuments, the stela of Hapu from Konosso explicitly states that these two kings ruled together for a while and that the regnal year 3 of Senusret II equates the regnal year 35 of Amenemhat II. Amenemhat's year 35 on the stela of Hapu is also the highest date known for him.