1.1 四元素的定義
Cayley-Dickson construction:
https://blog.csdn.net/sunqin_csdn/category_10016901.html
https://blog.csdn.net/weixin_32574873/article/details/103556842
https://blog.csdn.net/sunqin_csdn/article/details/108966950?utm_medium=distribute.pc_relevant.none-task-blog-2~default~baidujs_title~default-0.highlightwordscore&spm=1001.2101.3001.4242.1