https://www.pearltrees.com/u/75492848-mandarin-chinese-pinyin-chart
Mandarin Chinese Pinyin Chart with Audio - Yabla Chinese | Pearltrees
About Pinyin Hanyu Pinyin is the official system to transcribe Mandarin Chinese sounds into the Roman alphabet. It was invented in 1950s, and adopted as a
mandarin chinesepinyin chartwith audiopearltrees