Chāndogya Upaniṣad 1.3.4

1.3.4

yā vāk sark \
tasmād aprāṇann anapānann ṛcam abhvyāharati \
yark tat sāma \
tasmād aprāṇann anapānan sāma gāyati \
yat sāma sa udgīthaḥ \
tasmād aprānann anapānann udgāyati \\103.4\

4. The Ṛic is speech. Therefore one utters the Ṛic without in-breathing, without out-breathing. The Sāman is the Ṛic. Therefore one sings the Sāman without in-breathing, without out-breathing. The Udgītha is the Sāman. Therefore one chants the Udgītha without in-breathing, without out-breathing.