2. Sci-tech periodicals: Each periodical has a fixed name and format, and a continuous publication serial number, which is edited and published by a special editing institution. Compared with books, the publishing cycle is short, the publishing speed is fast, the quantity is large, and the content is novel and rich.
Third, patent literature: a large number, fast reporting, wide subject areas, novel content, practical and reliable. Due to these characteristics of patent documents, their scientific and technological information value is increasing, and the utilization rate is also increasing.
Four, scientific and technological report: a separate book, the reported results must generally be approved by the competent department to organize the relevant units, its content is in-depth, reliable, detailed, and not limited by space, strong operability, rapid report. Some reports are generally controlled because they involve cutting-edge technology or national defense issues.
5. Dissertation: theoretical and systematic, with specific content, detailed elaboration and certain originality, it is an important source of literature information.
6. Conference documents: timely dissemination of information, focused topics, novel content, strong professionalism and high quality, often representing the latest academic research achievements in a certain discipline or professional field, and basically reflecting the academic level, research trends and development trends of the discipline or profession.
Seven, government publications: the content is reliable, and there is some duplication with other sources of information. With the help of government publications, we can learn about a country's science and technology policies and economic policies. It has certain reference function for understanding its scientific and technological activities and achievements.