One verse

Srimad Bhagavatam 12.6.78

12.6.78

उदीच्या: सामगा: शिष्या आसन् पञ्चशतानि वै । पौष्यञ्ज्यावन्त्ययोश्चापि तांश्च प्राच्यान् प्रचक्षते ॥ ७८ ॥

udīcyāḥ sāma-gāḥ śiṣyā āsan pañca-śatāni vai pauṣyañjy-āvantyayoś cāpi tāṁś ca prācyān pracakṣate

udīcyāḥ
belonging to the north
sāma-gāḥ
the singer of the Sāma Veda
śiṣyāḥ
the disciples
āsan
there were
pañca-śatāni
five hundred
vai
indeed
pauṣyañji-āvantyayoḥ
of Pauṣyañji and Āvantya
ca
and
api
indeed
tān
they
ca
also
prācyān
easterners
pracakṣate
are called

The five hundred disciples of Pauṣyañji and Āvantya became known as the northern singers of the Sāma Veda, and in later times some of them also became known as eastern singers.