Abu Dawud Book 3, Hadith Number 1571.

Narated By Mu’adh ibn Jabal : When the Prophet (PBUH) sent him to the Yemen, he ordered him to take a male or a female calf a year old for every thirty cattle and a cow in its third year for every forty, and one dinar for every adult (unbeliever as a poll-tax) or cloths of equivalent value manufactured in the Yemen.