成唯識論述記 4.966

4.966

述曰：言五根者，以不共故，餘識不依故，一也。又此必與五識同境，二也。此又相近，餘依遠故，三也。又此相順，餘境別故，四也。所以不說餘之三依，下第二段也。

The Commentary states: As for the five faculties: first, because they are uncommon (asādhāraṇa), the other consciousnesses do not rely on them. Second, they definitely share the same intentional object as the five consciousnesses. Third, they are immediate, whereas the other supports are distant. Fourth, they conform [to the consciousness], whereas the objects of the others differ. This is why the other three supports are not mentioned; this is the second section below.