Li Fang-Kuei
In the early 1970s, Li Fang-Kuei used an amended version of Karlgren's transcription as a point of departure for his reconstruction of Old Chinese phonology. Li addressed some of the criticisms of Karlgren's system, revising some initials and distinguishing finals that Karlgren had combined. Although Karlgren's view of Middle Chinese as a single spoken variety is no longer widely held, his transcription, as revised by Li, is still widely used as a notation for the "Qieyun" categories.