維摩經玄疏 1.119

1.119

龍樹菩薩造《正觀論》，用四番四悉檀，三番正通釋諸摩訶衍三教，一番傍釋三藏生滅因緣教也。

Bodhisattva Nāgārjuna composed the Mūlamadhyamakakārikā, using four turns of the four siddhāntas: three turns directly and thoroughly explain the three teachings of the various Mahāyānas, while one turn secondarily explains the Tripiṭaka teaching of conditioned arising and ceasing.