https://www.birmingham.ac.uk/news-archive/2017/the-forgotten-history-of-beijings-first-forbidden-city
The forgotten history of Beijing's first forbidden city - University of Birmingham
Medieval History doctoral researcher Jonathan Dugdale writing for The Conversation.
history of beijingthe forgottenforbidden city
https://www.globaltimes.cn/page/202212/1281877.shtml
Shangzhai Ruins: Stonework reveals archaeological history of Beijing - Global Times
Shangzhai Ruins: Stonework reveals archaeological history of Beijing Located in the Pinggu district of Beijing, the Shangzhai Ruins tell a story about the...
history of beijingshangzhairuinsstoneworkreveals