אֵ֣לֶּה הֵ֞ם בְּנֵ֤י יִשְׁמָעֵאל֙ וְאֵ֣לֶּה שְׁמֹתָ֔ם בְּחַצְרֵיהֶ֖ם וּבְטִֽירֹתָ֑ם שְׁנֵים־עָשָׂ֥ר נְשִׂיאִ֖ם לְאֻמֹּתָֽם׃
these are the sons of Ishmael, and these are their names, by their villages, and by their encampments; twelve princes according to their nations.
Read midrashic interpretation of Genesis 25:16: and classical rabbinic exegesis.