Sekhiyakaṇḍa

Vinayapiṭaka · Parivāra · Vol. 8 · Section 452

[452] Out of disrespect (anādariya), one teaching the Dhamma to a person whose head is wrapped in a turban commits one offence (āpatti): an offence of wrong-doing (dukkaṭa).

English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.

This passage also appears in 5 other places