SB 5.20.39

tad-upariṣṭāc catasṛṣv āśāsvātma-yoninākhila-jagad-guruṇādhiniveśitā ye dvirada-pataya ṛṣabhaḥ puṣkaracūḍo vāmano ’parājita iti sakala-loka-sthiti-hetavaḥ.
Synonyms: 
tat-upariṣṭāt — on the top of Lokāloka Mountain; catasṛṣu āśāsu — in the four directions; ātma-yoninā — by Lord Brahmā; akhila-jagad-guruṇā — the spiritual master of the whole universe; adhiniveśitāḥ — established; ye — all those; dvirada-patayaḥ — the best of elephants; ṛṣabhaḥ — Ṛṣabha; puṣkara-cūḍaḥ — Puṣkaracūḍa; vāmanaḥ — Vāmana; aparājitaḥ — Aparājita; iti — thus; sakala-loka-sthiti-hetavaḥ — the causes of the maintenance of the different planets within the universe.
Translation: 
On the top of Lokāloka Mountain are the four gaja-patis, the best of elephants, which were established in the four directions by Lord Brahmā, the supreme spiritual master of the entire universe. The names of those elephants are Ṛṣabha, Puṣkaracūḍa, Vāmana and Aparājita. They are responsible for maintaining the planetary systems of the universe.