維摩經玄疏 6.71

6.71

三、明用悉檀起有無門，類前有門，用四悉檀意，則有空門得起，故為《昆勒論》所通也。

Third, explaining the use of the siddhāntas to generate the door of both existence and emptiness: analogous to the door of existence above, by using the intention of the four siddhāntas, the door of both existence and emptiness can arise; hence it is accessed by the Peṭaka treatise.