当文内引用采用文献号，则以数字顺序在文内和文后列出文献。
文献可以各种方式置于文中，但是必须具体有意义。
大体来说，根据想强调的内容，文献可在引用的内容或作者姓名之后出现。例如：
1）Starfishfertilization is species specific (17).
2）Peterson (17) reported that starfishfertilization is species specific.
标注注意事项：
不要将文献放置在某项内容的中间或某项研究的概括信息之后。
例如：In a current study (16), proteins expressed by the Epstein-Barr virus have beenclassified into three general groups according to their kinetics and synthesisrequirements.
应修改为：In a current study, proteins expressed bythe Epstein-Barr virus have been classified into three general groups accordingto their kinetics and synthesis requirements (16).
文献并不一定要放置在句尾。为区分作者的研究和他人的研究，应将文献放在相应的研究成果后面，而不是整个研究后面。
例如：The Mo+PyF101 M-MuLV used in this study was obtained from the supernatantof the 25-3 cell line confluently infected with the virus (3).
应修改为：TheMo+PyF101 M-MuLY(3) used in this study was obtained from the supernatantof the 25-3 cell line confluently infected with the virus.
寻找美食的虫
