https://johncarlosbaez.wordpress.com/2023/08/05/nortons-dome/

https://sites.pitt.edu/~jdnorton/Goodies/Dome/

https://en.维基.org/wiki/Picard%E2%80%93Lindel%C3%B6f_theorem#Example_of_non-uniqueness
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修改:vinbo FROM 202.121.181.*
FROM 202.121.181.*