Vinaykathā

Vinayapiṭaka · Cūḷavagga (2) · Vol. 7 · Section 289

[289] Then it occurred to the bhikkhus: "What, then, is the minimum size of a long seat (dīghāsana)?" … "Bhikkhus, I allow that a long seat, at its minimum, is one large enough for three."

English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.