The dblp computer science bibliography provides more than 5 million hyperlinks for research publications. Most of those links point to article landing pages within a publisher’s digital library. A growing number of publishers have adopted the open access model of publishing, thereby allowing the dissemination of research results free of cost and without any access barrier. You may have noticed that we have recently begun to mark such hyperlinks in dblp with a special orange badge signalling their availability. (Please also note that this badge is still work in progress, and that there are still plenty of openly accessible articles in dblp that go unrecognized.)

However, most publishers in computer science do still demand an active subscription or a fee for access to research articles. Due to the way dblp collects its metadata, these paywalled document locations are usually the only ones that are listed in dblp. But thanks to the API of Unpaywall, in many cases, we are now able to provide an open alternative.

Integration of Unpaywall data

Unpaywall was launched in 2017 by Heather Piwowar and Jason Priem as a free browser extension that allows researchers to legally bypass the publishers’ paywall by retrieving openly accessible versions of scholarly publications. This includes independently archived author copies (e.g., hosted on an institute’s web server), preprints in open repositories, or open full versions of paywalled extended abstracts. In this relatively short time, Unpaywall has received considerable attention and has already been referenced in dozens (if not hundreds) of publications. Currently, the database lists about 25 million openly accessible documents across all scholarly disciplines, with a fair number of them being computer science publications. Besides providing a REST API, Unpaywall data is also available as complete database snapshots.

Since the integration of Unpaywall at dblp relies on external API calls from your browser (which might be a privacy consideration for you), you will need to opt-in once before any data can be retrieved. You can find the option to enable “unpaywalled article links” in the user settings menu in the top-right corner. While we do not have any reason to believe that your connection data will be misused, we do not have any control over the remote servers either. So please proceed with care and consider checking the Unpaywall privacy policy.

Once enabled, the dblp website will automatically look for openly accessible versions of paywalled articles while you are browsing dblp. The links to those unpaywalled versions will be dynamically added to a publication’s usual list of external links, together with a small green marker.

Since there is a slight delay when contacting the live API, please don’t be surprised if you see such green badges suddenly pop up while you are browsing. We hope that this new integration will make it even easier for you to access publications via dblp.