成唯識論述記 1.336

1.336

此約影像，依他為相。若約所執，當情顯現，亦名為相。緣第八者，即是本質。下准此知，相亦有二。

This is in terms of the reflective image, taking the paratantra as the mark. If it is in terms of what is grasped, appearing directly to consciousness, it is also called a mark. That which conditions the eighth is the original referent (bimba). Understand accordingly below that 'mark' (nimitta) also has two meanings.