VaggaDibbasotakathā

Abhidhammapiṭaka · Kathāvatthu · Vol. 37 · Section 816

[816] "Having been of the form sphere (rūpāvacara), does it become of the formless sphere (arūpāvacara)?" — "Yes." "Having been included (pariyāpanna), does it become not included (apariyāpanna)?" — "It should not be said thus." …

English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.

This passage also appears in 5 other places