There are two ways to publish papers in general international conferences, one is electronic version, and the other is paper version. The electronic version is usually sent to the author in the form of a CD. Some CDs only contain the contents of papers in PDF format, and one or several articles are put in a PDF, while others are made into a better multimedia format, which is convenient for browsing and searching. Such a multimedia CD can generally solve the front cover, back cover and directory page of PDF.

The other is a paper version, which is printed by a traditional publishing house and needs to be scanned by itself.

In addition, some papers may not be provided, but only collected by retrieval institutions, such as EI and ISTP, so if you have an account of a research institution or university, some of them can log in and download, but these papers are often single papers without any front cover or back cover catalogue.