The order of symbols in papers usually follows the international standard, that is, APA format. In APA format, references should be arranged alphabetically according to the author's surname. For example, if you cite three papers with authors A, B and C, you should list them in the following order:

-A, B. (Year). title of article. journal name, Vol.X, Noy, PP. Z-X。

-C. (year). title of article. journal name, Vol.X, Noy, PP. Z-X。