Mahabharata Udyoga Parva (Uluka Dutagamana Parva) Chapter 199:2
And he was followed by Sauchitti, who steadily adhered to truth and was invincible in battle, and Srenimat, and Vasudeva and Vibhu, the son of the ruler of Kasi, with twenty thousand cars, and hundred million steeds of high mettle, each bearing scores of bells on its limbs, and twenty thousand smiting elephants with tusks as long as plough-shares, all of good breed and divided temples and all resembling moving masses of clouds. Indeed, these usually walked behind those monarchs. Besides these, O Bharata, the elephants that Yudhishthira had in his seven Akshauhinis, numbering seventy thousand with humour trickling down their trunks and from their mouths, and resembling (on that account) showering clouds, also followed the king, like moving hills.
Thus was arrayed that terrible force of the intelligent son of Kunti. And relying upon that force he battled with Suyodhana, the son of Dhritarashtra. Besides those already named, other men by hundreds and thousands and tens of thousands, in divisions numbering by thousands, followed (the Pandava army), roaring loudly. And the warriors by thousands and ten thousands, filled with joy, beat their drums by thousands and blew conchs by tens of thousands!" The End of Udyoga Parva