What is Matsui Version (Version Problem)

As far as I know, most of the earliest Beijing-Song editions were aimed at Song editions, and some later editions were distinguished by this name. In the antique appraisal, there are a large number of Beijing-Song engravings in the late Qing Dynasty and the Republic of China, which copied the Song edition books and claimed to be Song edition books to make huge profits. As many people know, since the compilation of Si Ku Quan Shu flourished in Liulichang, Beijing, most rare ancient books from Song Dynasty to Ming Dynasty have been collected here, and most of them are books from Song Dynasty, so they are more accurate and precious. The Song Dynasty ruled the world with culture, and the poems of Tang and Song Dynasties affirmed the literary achievements of these two dynasties, so I think it is also for this reason that they are marked in Sikuquanshu.