Wong Shik Ling (also known as S. L. Wong) published a scheme of phonetic symbols for Cantonese based on the International Phonetic Alphabet (IPA) in the book "A Chinese Syllabary Pronounced according to the Dialect of Canton". The scheme has been widely used in Chinese dictionaries published in Hong Kong. The scheme, known as S. L. Wong system (), is a broad phonemic transcription system based on IPA and its analysis of Cantonese phonemes is grounded in the theories of Y. R. Chao.