CALIS Academic Conference Library. I really strongly recommend this. I'm totally aware of that. Although I don't need it myself, after all, I don't need it, but my sister will use it. According to my sister's evaluation, it is also very good.

1, scientific center

The founder of this website is Alexandra Elbakyan, the goddess of scientific research. She was selected as one of the top ten scientific figures in Nature 20 16. 90% of all kinds of English literature we read in major journals can be downloaded from this website. Generally, it can be found by document name, URL (document address), PMID (document unique identification code) or DOI number of the article.

2. Palm Bridge scientific research

At present, there are 7 15860 13 Chinese documents, which are updated by 3582289 every month; There are 54,457,774 foreign documents, and 5,557,504 are updated every month, including foreign periodicals, foreign conferences, foreign OA documents, foreign degrees, American government science and technology reports, and foreign military defense science and technology reports.

Foreign literature integrates the international mainstream English literature database, covering foreign literature resources such as Springer, Elsevier, Wiley, IEEE and AIAA. It can achieve one-click cross-database retrieval, direct local access to services, and most importantly, it also has the function of machine translation!