What symbols are used to identify source materials in papers?

References: References refer to the research results of others. The citations are marked with square brackets and the content is placed at the end of the article. Multiple citations from the same document should use the same serial number in the "References" and identify different page numbers at different locations in the text. The format is as follows:

(1) Monograph (M), Proceedings (C), Dissertation (D), Report (R)

[1] Liu Guojun, Chen Shaoye, Wang Fengzhu .Library Catalog[M].Beijing: Higher Education Press, 1957.15-18. (The page number of the monograph is in the text, such as [1]P (15-18))

(2) Journal article ( J)

[2] He Lingxiu. Reading Gu Cheng's "History of the Southern Ming Dynasty" [J]. Research in Chinese History, 1998, (3): 167-173.

[3] Jin Xianhe, Wang Changchang, Wang Zhongdong, et al. A... technology [J]. Journal of Tsinghua University (Natural Science Edition), 1993, 33(4): 62-67.

(3) Proceedings Precipitation literature (A)

[4] Zhong Wenfa. Application of nonlinear...[A]. Zhao Wei. The theory and application of operations research - Proceedings of the Fifth Congress of the Chinese Operations Research Society [C]. Xi'an: Xi'an University of Electronic Science and Technology Press, 1996.468-471.

(4) Newspaper article (N)

[5] Chen Sha. The vitality of knowledge[N ]. People's Daily, 2002-12-24(09).

(5) Various undefined documents [Z]

(6) Electronic documents:

[6] Wang Mingliang. On the progress of standardized database projects for Chinese academic journals [EB/OL].www.cajcd.edu.cn/pub/wml.txt/980810-2.html,1998-08-15/ 1998-10-04.

[7] Wan Jinkun. Abstracts of Chinese University Journal Papers (1983-1993). English version [DB/CD]. Beijing: China Encyclopedia Publishing House.