成唯識論述記 5.56

5.56

述曰：不假五引，故用前自類為開導依。五位無心時，或第七、八為依，例與五依故。

The Commentary states: It does not require induction by the five, and therefore uses the preceding [mind] of its own category as its basis of opening and guiding. In the five mindless states, sometimes the seventh and eighth serve as its basis, by analogy with giving the five their basis.