1 Chronicles 12:4

And Ismaiah the Gibeonite, a mighty man among the thirty, and over the thirty; and Jeremiah, and Jahaziel, and Johanan, and Josabad the Gederathite,

Cross-references

1 Chronicles 11:15 describes three of the thirty mighty men; Ishmaiah is said to be 'over the thirty' in 12:4, directly linking to that group.