成唯識論述記 3.184

3.184

述曰：識受等體各是一故，而相狀別，識、受、想等體性、相狀各各別故。行相言似，不言等者，據相似故，相似、等義無有差別。

The Commentary states: Because the substances of vijñāna, vedanā, and so on are each one, yet their marks and aspects are distinct, because the substances and mark-aspects of vijñāna, vedanā, saṃjñā, and so on are each distinct. As for the ākāra, it says "similar" and not "equal" because it is based on resemblance; between resemblance and equality, there is no difference in meaning.