Ramayana
नान्यं पश्यामि भैषज्यमन्तरा वृषभध्वजम् । नाश्वमेधात्परो यज्ञः प्रियश्चैव महात्मनः । तस्माद्यजामहे सर्वे पार्थिवार्थे दुरासदम् ॥ 7-90-12 ॥
"I see no other remedy save the god whose banner bears the bull. There is no sacrifice higher than the horse-sacrifice, and it is dear to the great-souled one. Therefore let us all perform, for the king's sake, that rite hard for others to accomplish."
english translation