成唯識論掌中樞要 2.19

2.19

There are four Sarvāstivādins. Here there are four kinds: differences of genre (bhāva), characteristic (lakṣaṇa), state (avasthā), and relativity (anyathātva). The third, positing the time periods based on functional activity (kāritra), is the most excellent, as in the twentieth fascicle of the Kośa.