Mimamsashastrasarvasva 3.4

3.4

athavā manvādismṛtayo'pyatrodāharaṇam | yadvā aṅgānyatrodāharaṇam | śākyādigranthā vā | “ tadetāni catvāryapi vicārasthānāni samānanyāyāni saha vicāryante—kimeṣāṃ svātantryeṇa
prāmāṇyaṃ naveti² ” tatra śākyādivyatiriktānāṃ prāmāṇyaṃ tāvadavagītameva | tatkimeṣāmevāpauruṣeyatvaṃ vedatvaṃ vā kalpyaṃ uta vedamūlakatvamiti saṃśaye—
“ vedaṃ hi kalpayitvaibhyaḥ punastasyāpi nityatā
vaktavyaiva varaṃ tena sā teṣvevāvadhāritā

Alternatively, the smṛtis of Manu and others are also the example here. Or the auxiliary limbs are the example here. Or the texts of the Śākyas and others. “Therefore, all these four topics of enquiry, being governed by the same principle, are enquired into together: Do these possess authority independently, or not?” (2) There, the authority of those other than the Śākyas and the like is indeed uncontested. Then, in the doubt whether authorlessness or status as Veda should be assumed for these themselves, or being rooted in the Veda:
“For having assumed a Veda from these, again its eternity
must also be stated; better therefore that it is established in them themselves.