CHĀNDOGYA UPANISHAD · 4.16.2

तयोर् अन्यतरां मनसा संस्करोति ब्रह्मा ।
वाचा होताध्वर्युर् उद्गातान्यतराम् ।
स यत्रोपाकृते प्रातरनुवाके पुरा परिधानीयाया ब्रह्मा व्यववदति ॥

tayor anyatarāṃ manasā saṃskaroti brahmā ।
vācā hotādhvaryur udgātānyatarām ।
sa yatropākṛte prātaranuvāke purā paridhānīyāyā brahmā vyavavadati ॥

The Brahman priest performs one of them in his mind, the Hotri, Adhvaryu, and Udgâtri priests perform the other by words. When the Brahman priest, after the Prâtaranuvâka ceremony has begun, but before the recitation of the Paridhânîyâ hymn, has (to break his silence and) to speak,

F. Max Müller · The Upanishads, Sacred Books of the East 1 (1879)