Books belong to red bones, all of which are bone marrow findings. The batch number of the library book is the import packaging type of the drug standard document. The English writing of the catalogue file is the international non-patented name. The first prescription in the second part is limited to the essence of medicine. Such as: book monographs, reviews, manuals and yearbooks, encyclopedias, standard materials and databases. , all belong to the third literature. Generally, the three documents are comprehensive, systematic and have a wide range of knowledge, and some of them also have retrieval functions.