Brahma Sutras
ॐ स्तुतिमात्रमुपादानादिति चेन्नापूर्वत्वात् ॐ ॥ ३-४-२१॥
If it be contended that texts (about Udgitha etc.) are merely eulogistic, because of having been accepted as subservient to ritual acts, then not so, because of the extra-ordinariness (of the texts).
english translation
OM stutimAtramupAdAnAditi cennApUrvatvAt OM ॥ 3-4-21॥
hk transliteration by Sanscript