* * * There are three volumes, each with more than 600 pages. Whether you study advanced mathematics, mathematical analysis or calculus in the future, this is an encyclopedia-style classic textbook with a lot of information and examples. In the process of calculus learning, it can be used as both a teaching material and a dictionary reference book.

If you are strict with yourself, you can also look at zorich's mathematical analysis, which is more abstract but closer to modern mathematics.

PS: Tongji version 6 is like a piece of shit. Don't buy it. What should be made clear in that book is not clear. Unclear things are repeatedly quoted in subsequent chapters. When I was a sophomore, I saw that set of books was not shallow.