Jaiminīya Upaniṣad Brāhmaṇa 3.37.8

3.37.8

tad etad abhrātṛvyaṃ sāma
na ha vā indraḥ kaṃ cana bhrātṛvyam paśyate
sa yathendro na kaṃ cana bhrātṛvyam paśyata evam eva [na] kaṃ cana bhrātṛvyam paśyate ya etad evaṃ vedātho yasyaivaṃ vidvān udgāyati /
ṣaṣṭhe 'nuvāke navamaḥ khaṇḍaḥ /
ṣaṣṭho 'nuvākas samāptaḥ //

This is the rival-free sāman. Indra indeed sees no rival. Just as Indra sees no rival, even so he sees [no] rival who knows this thus, and also he for whom one who knows thus sings the udgītha. / Ninth subsection in the sixth anuvāka. / The sixth anuvāka is finished.