Every English periodical has different marking methods. Some periodicals only have volume numbers and no issue numbers, while domestic periodicals have both volume numbers and issue numbers. Papers that have been successfully submitted but not officially published have DOI numbers, which can also be found in the database, without volume numbers and page numbers.
Literature refers to books, periodicals and regulations with historical significance or research value. It is the final expression of scientific research and technological research achievements, and it is an important medium for people to acquire knowledge.