更改

已由三奇同学完成第一次审校。

已由三奇同学完成第一次审校。

[[Image:ouroboros.png|thumb|古代的符号[[衔尾蛇，一条吞噬自己尾巴的蛇，表示自指]].<ref>{{cite web |last1=Soto-Andrade |first1=Jorge |last2=Jaramillo |first2=Sebastian |last3=Gutierrez |first3=Claudio |last4=Letelier |first4=Juan-Carlos |title=Ouroboros avatars: A mathematical exploration of Self-reference and Metabolic Closure |url=https://mitpress.mit.edu/sites/default/files/titles/alife/0262297140chap115.pdf |publisher=MIT Press |accessdate=16 May 2015}}</ref>]]

[[Image:ouroboros.png|thumb|古代的符号衔尾蛇，一条吞噬自己尾巴的蛇，表示自指.<ref>{{cite web |last1=Soto-Andrade |first1=Jorge |last2=Jaramillo |first2=Sebastian |last3=Gutierrez |first3=Claudio |last4=Letelier |first4=Juan-Carlos |title=Ouroboros avatars: A mathematical exploration of Self-reference and Metabolic Closure |url=https://mitpress.mit.edu/sites/default/files/titles/alife/0262297140chap115.pdf |publisher=MIT Press |accessdate=16 May 2015}}</ref>]]