Canto 1 - Boyhood
Bāla-kāṇḍa
Chapter 14: The Aśvamedha Sacrifice
Text 1.14.8

आह्वयां चक्रिरे तत्र शक्रादीन्विबुधोत्तमान्।
ऋश्यशृङ्गादयो मन्त्रैः शिक्षाक्षरसमन्वितैः॥

āhvayāṁ cakrire tatra śakrādīn vibudhottamān
ṛśyaśṛṅgādayo
mantraiḥ śikṣākṣara-samanvitaiḥ

āhvayām cakrire tatra = called for; śakra-ādīn = Indra and other; vibudha-uttamān = excellent intelligent demigods; ṛśyaśṛṅga-ādayaḥ = Ṛśyaśṛṅga and others; mantraiḥ = with mantras; śikṣā-akṣara-samanvitaiḥ = in line with proper principles of syllabic utterances.

Ṛśyaśṛṅga and others called for Indra and other excellent intelligent demigods with mantras in line with proper principles of syllabic utterances.