The Collation of Variant Readings in the *Mahāprajñāpāramitāsūtra 大般若経校異, edited by the Rinzai monk Shaku Sohō 釈祖芳 (1722–1806), examines six editions of Xuanzang’s translation of the text. Sohō used a printed edition made by Nakano Zeshin 中野是心 (?–1675) as his basic text, with which he compared five other versions. These include two old Japanese manuscripts, i.e. the so-called Nanto 南都 edition and the Shinsen 神泉 edition, as well as three woodblock print editions. The collation of two old Japanese manuscripts, whose variant readings are not recorded in the Taishō Canon, makes the text a very important source for the study of the Chinese translation of the *Mahāprajñāpāramitāsūtra.
