Cross reference
Judges 12:9
9 And he had thirty sons; and thirty daughters he sent abroad, and thirty daughters he brought in from abroad for his sons. And he judged Israel seven years.
Judges 10:4
4 And he had thirty sons that rode on thirty ass colts, and they had thirty cities, which are called Havvoth-jair unto this day, which are in the land of Gilead.
Judges 12:14
14 And he had forty sons and thirty sons' sons, that rode on threescore and ten ass colts: and he judged Israel eight years.