Yes, if it is data, Lang Xianping is also obtained directly or through calculation from other places. You'd better find its source.

If you can't find it, you can also quote it, and standardize the reference format according to the information obtained from the Internet, specifically the article name, author, website and website name. The specific requirements vary from school to school. Please refer to the school paper standard or the paper reference standard for publishing periodicals.

If it's a graduation thesis, it's best to seek the positive opinions of the tutor.