Aśauca-vidhi (Rules of Impurity) within Śrāddha-kalpa — Chapter on Testing/Selecting Brahmanas and Honoring the Atithi
अन्तर्जानूपविष्टेन तद्वदाचमनं भवेत् / मुण्डाञ्जटिलकाषायाञ्श्राद्धकर्मणि वर्जयेत्
antarjānūpaviṣṭena tadvadācamanaṃ bhavet / muṇḍāñjaṭilakāṣāyāñśrāddhakarmaṇi varjayet
Seated with the knees drawn inward, one should perform ācaman in that manner; and in the śrāddha rite one should avoid the shaven-headed, the jaṭā-wearers, and those in kāṣāya robes (marks of renunciation).