legal ground
Article 22 of the Copyright Law of People's Republic of China (PRC) is under any of the following circumstances: (1) To study, research or enjoy the use of other people's published works for individuals; (2) appropriately quoting published works of others in works for the purpose of introducing and commenting on works or explaining problems. Article 23 When compiling and publishing textbooks for the implementation of the nine-year compulsory education and the national education plan, unless the author declares in advance that they are not allowed to be used, published pieces of works, short stories, musical works or single works of art and photography may be incorporated into the textbooks without the permission of the copyright owner, but remuneration shall be paid in accordance with the regulations. Marking the name of the author and the name of the work shall not infringe upon other rights enjoyed by the copyright owner in accordance with this Law.