Chandogya Upanishad 1.98

ते ह यथैवेदं बहिष्पवमानेन स्तोष्यमाणाः सꣳरब्धाः सर्पन्तीत्येवमाससृपुस्ते ह समुपविश्य हिं चक्रुः ॥ ४ ॥

1.12.4 — te ha yathaivedam bahishpavamanena stoshyamanah samrabdhah sarpantityevamasasripuste ha samupavishya him chakruh || 4 ||

The dogs came on, holding together, each dog keeping the tail of the preceding dog in his mouth, as the priests do when they are going to sing praises with the Vahishpavamâna hymn. After they had settled down, they began to say Hin.

जैसे बहिष्पवमान-स्तोत्र से स्तुति करने वाले ऋत्विक् एक-दूसरे से जुड़कर संसृप्त होकर चलते हैं, वैसे ही वे श्वान संसृप्त होकर आए, और बैठकर उन्होंने 'हिं' ध्वनि की।