Students need to quote some literature when writing their graduation thesis, and there are often many different letters in the references. What do these letters represent respectively? The editor of this issue tells you.

　　The reference letters represent the following meanings: a (monograph, separated literature in the collection of papers), m (Monograph), C (collection of papers), n (newspaper articles), J (journal articles), D (Dissertation), R (report), s (standard).

　　References are the overall reference or reference of a certain work or paper in the process of academic research. The cited documents have been noted in the notes and no longer appear in the references after the text.

　　Some letters appear in the references, and some people don't know what it means. Today, I will briefly introduce the reference type identification code and the corresponding Chinese meaning:

　　① M (Monograph): monograph; ② C (Collection): collection of papers; ③ (News): n newspaper article; ④ J (Journal): journal articles; ⑤ D (degree): dissertation ⑥ R (report): report; ⑦ S (standard): standard; ⑧ P (patent): patent; ⑨ A (article): precipitated documents in monographs and papers.