Kaṭhinavagga

Vinayapiṭaka · Parivāra · Vol. 8 · Section 261

[261] One who lets an extra robe (atirekacīvara) pass beyond ten days commits one offence (āpatti): a pācittiya offence entailing relinquishment (nissaggiya pācittiya).

English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.

This passage also appears in 1 other place

Vol. 8 · Section 281 — Pattavagga