Perma.cc was developed by the Harvard Innovation Lab to prevent "link rot" (the dreaded "page not found" or 404 error). Websites and webpages are constantly changing, with content being removed, updated, or moved elsewhere. Prior to Perma.cc, this was a major problem because many of the URLs that appeared in the citations of an article would no longer work by the time that article was published.
Perma.cc allows users to preserve links by making archival copies of webpages. With a Perma.cc link, future readers will always be able to see what a webpage looked like when the link was created, even if the webpage is subsequently modified or removed. Perma.cc has allowed authors and student editors to feel much more confident about relying on electronic sources in citations. The Bluebook encourages archiving links in Rule 18.
A Perma.cc link will preserve the entire webpage, not just a screenshot of what is visible on the screen. Click here for an example of a page preserved using Perma.cc. The service was launched in Fall 2013 and has been widely adopted. Today, more than 150 law journals use Perma.cc to prevent link rot.
1. Prevent link rot.
Webpages are frequently removed or taken down. A study published in the Harvard Law Review Forum in 2014 indicated that "more than 70% of the URLs within [the three law journals that were the focus of the study: Harvard Law Review, Harvard Journal of Law and Technology, and Harvard Human Rights Journal], and 50% of the URLs within U.S. Supreme Court opinions suffer reference rot--meaning, again, that they do not produce the information originally cited." (Perma.cc link of this study available here.)
Similar to how your journal pulls copies of all of the cited sources in an article to check the support for the author's assertions during the production process, readers also need to or want to refer to the sources relied upon by authors. Archiving URLs will increase your journal's credibility and an author's credibility because readers will always be able to confirm with the original source that it actually said what the author claims. Archiving URLs will also decrease frustration for readers because they will no longer encounter dead links after following the URLs in the citations.
2. Preserve a version of a webpage as it appeared on the archival date.
Webpages are frequently modified or updated. For instance, an author might rely on a webpage that sets out a policy or provides data, but the company or organization maintaining the website may update that policy or data in the future by overwriting the previous policy or data without maintaining an archive of the previous version. Consequently, if a reader were to follow the URL in the citation, he or she would see a new policy or data different from what the author had actually relied on to support his or her points in the article. Perma.cc allows you to retain a copy of the webpage exactly how it appeared on the date in which the webpage was archived.
3. Increase access to sources for readers and ensure the long term value of your journal as a research resource.
Although your journal may retain files of all of the sources pulled during the source pulling phase of production, these files are only accessible to your journal members. Perma.cc helps make cited electronic sources easily available for all current and future readers because anyone can view the Perma.cc links.
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