First-class literature is based on the achievements of scientific experiments and production practice, including periodical papers, scientific reports, conference papers, dissertations and patents.
The second article
Secondary literature is a variety of retrieval tools, such as catalogues, bibliographies, abstracts, etc., after processing and sorting out primary information. It does not provide comments, but only provides search clues for literature.
Three documents
The three documents are comprehensive research or reference tool documents based on a large number of original documents, which are written after comprehensive analysis and research.
Relationship between documents
From the first-class literature to the third-class literature, it is a process from extensive to limited, from decentralized to centralized, from disorder to system, and it is also a process from disorder to order, from one orderly structure to another perfect orderly structure of scientific and technological literature resources.
Utilize literature resources
Using these three kinds of documents, we can better understand the achievements of scientific experiments and production practices, sort out and retrieve information, and make comprehensive analysis and research on these information, so as to make better use of scientific and technological literature resources.