A closer look at the Sci-Hub corpus: what is being downloaded and from where?

Sci-Hub remains among the most common sites via which readers circumvent article paywalls and access scholarly literature. But where exactly are its download requests coming from? And just what is being downloaded? Bastian Greshake has analysed the full Sci-Hub corpus and its request data, and found that articles are being downloaded from all over the world, more recently published papers are among the most requested, and there is a marked overrepresentation of requested articles from journals publishing on chemistry.