The Law Code of Devala 7.9: Nirṇayasindhu · Ācārabhūṣaṇa · Saṃskāraratnamālā (Gopīnātha Dīkṣita Oka)

7.9

upavītaṃ vaṭor ekaṃ dve tathetarayoḥ smṛte | ekam eva yatīnāṃ syād iti śāstrasya niścayaḥ

If what is undrinkable has been drunk, and what is inedible has been eaten, / and intercourse with an illicit woman has been performed by a Brahmin carried off by Mlecchas,

The student has one sacred thread, the other two (householder and hermit) two; ascetics have only one: this is the settled view of the treatise.