Zechariah 6:3
"And in the third chariot white horses; and in the fourth chariot grisled and bay horses."
Cross References (ranked by relevance)
And I saw, and behold a white horse: and he that sat on him had a bow; and a crown was given unto him: and he went forth conquering, and to conquer.
And I looked, and behold a pale horse: and his name that sat on him was Death, and Hell followed with him. And power was given unto them over the fourth part of the earth, to kill with sword, and with hunger, and with death, and with the beasts of the earth.
I saw by night, and behold a man riding upon a red horse, and he stood among the myrtle trees that were in the bottom; and behind him were there red horses, speckled, and white.
And I saw a great white throne, and him that sat on it, from whose face the earth and the heaven fled away; and there was found no place for them.
His legs of iron, his feet part of iron and part of clay.
And I saw heaven opened, and behold a white horse; and he that sat upon him was called Faithful and True, and in righteousness he doth judge and make war.