Gwoyeu Romatzyh
- basic comparison: Gwoyeu Romatzyh and tonal hanyu pinyin
- advanced comparison: Zhuyin Fuhao, Wade-Giles, MPS2, Yale, Tongyong Pinyin, Hanyu Pinyin, and Gwoyeu Romatzyh
- Gwoyeu Romatzyh tonal spelling conventions
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Y.R. Chao
November 3, 1892 - February 24, 1982