俱舍論頌疏論本 12.21

12.21

成中初劫起器世間，後十九中有情漸住，壞中後劫壞器世間，前十九劫有情漸捨，如是所說成、住、壞、空各二十中劫，積成八十，總此八十成大劫量。

During formation, the initial kalpa gives rise to the vessel world, and during the following nineteen [kalpas] sentient beings gradually abide. During dissolution, the final kalpa destroys the vessel world, and during the preceding nineteen kalpas sentient beings gradually leave. In this way, formation, duration, dissolution, and void, each having twenty intermediate kalpas, accumulate to eighty; in total, these eighty form the measure of a great kalpa.