S. L. Wong (phonetic symbols)
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.
Source: Wikipedia — S. L. Wong (phonetic symbols) (CC BY-SA 4.0)