וַיֵּרְד֡וּ שְֽׁלוֹשָׁה֩ מִן־הַשְּׁלוֹשִׁ֨ים רֹ֤אשׁ עַל־הַצֻּר֙ אֶל־דָּוִ֔יד אֶל־מְעָרַ֖ת עֲדֻלָּ֑ם וּמַחֲנֵ֣ה פְלִשְׁתִּ֔ים חֹנָ֖ה בְּעֵ֥מֶק רְפָאִֽים׃
Três dos trinta chefes desceram à penha; a ter com Davi, na caverna de Adulão; e o exército dos filisteus estara acampado no vale de Refaim.
Rashi on I Chronicles
And three of the thirty These three were the heads of the entire thirty.