John Gill Commentary 1 Chronicles 1:32

"And the sons of Keturah, Abraham`s concubine: she bare Zimran, and Jokshan, and Medan, and Midian, and Ishbak, and Shuah. And the sons of Jokshan: Sheba, and Dedan." — 1 Chronicles 1:32 (ASV)

(See Gill on 1 Chronicles 1:28).