1. There should be at least 40 Chinese documents.
2. There should be no less than 20 foreign documents. Total * * * should be no less than 60 articles.
3. The number of references in recent five years should generally be no less than 0/3 of the total number of 65438+, and there should be references in recent two years. Literature review is an important part of graduation thesis and an important way to reflect the scientific and rigorous nature of the thesis. When quoting references, we should pay attention to the following problems: references are limited to the main documents related to this article that the author has read personally, and the number of documents in the last three years should account for more than 30%, and the number of documents in the last five years should account for more than 50%, and should be carefully checked against the original text. Documents such as "internal materials", "to be published" and "conference materials" should not be introduced as references.