1. Direct quotation: This is the most common quotation method, which directly quotes the data or opinions in the original text intact. This method needs to use quotation marks at the end of the article and list references.

2. Indirect quotation: This method is to rewrite the data or opinions in the original text, but it still needs to indicate the source. This method does not need to use quotation marks, but it still needs to list references at the end of the article.

3. General quotation: This way is to summarize the data or opinions in the original text and then express them in your own words. This method does not need to use quotation marks, but it still needs to list references at the end of the article.

4. Data citation: This method refers to data directly, but does not need to refer to the whole article. At the end of the paper, the references should be listed, and the data sources should be indicated.

5. Chart citation: This method is to show the data through a chart, and then indicate the data source at the bottom of the chart. There is no need to list references in this way.

6. Network citation: This method refers to the data or information on the network, and the source and access date of the data need to be indicated at the end of the article.

No matter which citation method is adopted, we must abide by the principle of academic integrity and must not copy other people's research results. At the same time, we should also quote references correctly so that readers can consult the original materials. When quoting data, we should also pay attention to the reliability and accuracy of the data to avoid the deviation of the research results caused by wrong data.