Sanskrit (romanised) · Chāndogya Upaniṣad (Sanskrit, IAST)
etad gāyatraṃ prāṇeṣu protam
English · F. Max Müller
The hinkâra is mind, the prastâva speech, the udgîtha sight, the pratihâra hearing, the nidhana breath. That is the Gâyatra Sâman, as interwoven in the (five) prânas.