Mathematics textbooks are mainly advanced mathematics, advanced algebra and analytical mathematics. Advanced Mathematics is compiled by Northeastern University, edited by Che Xiangkai and Xie Chongyuan, and also published by Higher Education Press. You can look for it (of course, the best version is Tongji, and the advanced mathematics of Dongda University is much more than Tongji), as well as advanced algebra, which is Tongji's, and analytical mathematics.