It’s really important for consistency and usability that all members follow these guidelines. We rarely have to change them and usually only do so for very good reasons. Please note that this is for display of Crossref DOIs, not anyone else’s DOIs, as not all DOIs are made equal.
The goals of the guidelines are:
This page includes the following sections:
Crossref DOIs should always be displayed as a full URL link in the form
and should not be preceded by “doi:” or “DOI:”
These new guidelines have a two important changes from the previous guidelines:
Crossref DOIs should be displayed in the full URL form wherever bibliographic information about a piece of content is displayed.
An obligation of membership is that Crossref DOIs must be displayed on members’ response pages (also called landing pages). Crossref recommends that Crossref DOIs also be displayed or distributed in the following contexts:
Crossref members should not use proprietary, internal or other non-DOI URLs in citation downloads, metadata feeds to third parties or in instructions to researchers on how to cite a document.
Linking references in journal articles using Crossref DOIs is an obligation of membership and we strongly encourage you to link references in other content types. Because there are space constraints even in online references lists Crossref DOIs can be displayed in several ways, depending on the publisher’s preference and publication style. Crossref recommends the following options:
Option 1—Use the Crossref DOI URL as the permanent link
Soleimani N, Mohabati Mobarez A, Farhangi B. Cloning, expression and purification flagellar sheath adhesion of Helicobacter pylori in Escherichia coli host as a vaccination target. Clin Exp Vaccine Res. 2016 Jan;5(1):19-25. https://doi.org/10.7774/cevr.2016.5.1.19
Option 2—Display the text “Crossref” with a permanent DOI link behind the text
Galli, S.J., and M. Tsai. 2010. Mast cells in allergy and infection: versatile effector and regulatory cells in innate and adaptive immunity. Eur. J. Immunol. 40:1843–1851. Crossref
The International DOI Foundation created the ShortDOI service as an open system that creates shortcuts to DOIs, which can be long, and is similar to how URL shortening services work. For example, for the DOI https://doi.org/10.7774/cevr.2016.5.1.1 the short form is https://doi.org/bwfc. Only one ShortDOI is created for each DOI and the ShortDOI returns exactly the same results as the DOI. For more information go to http://shortdoi.org/. ShortDOIs are not widely used and we think it’s best to just create short DOIs in the first place. ShortDOIs are not DOIs themselves, which is confusing.
No - you can make the change for new content going forward and do not need to update existing PDF files. You can update existing content if you want but this is optional. The current form for DOI links using http://dx.doi.org will continue to work as long as Crossref and DOI System exist.
We have set the effective date for the new guidelines to be March 2017 to give people time to make changes but you can start using the new format right away if you like.
Some publishers have reported resistance from colleagues to the idea that when the DOI is displayed on the landing page - that is, the page the DOI links to - it should be a link. It should be because the DOI is both an identifier and a persistent link and it will be easier for users to always display the DOI as a full link so it can be copied easily. In addition, many users won’t know what a DOI is but they know what a link is and we want to encourage the DOI to be used as a persistent link and to be shared and use in other applications (e.g. reference managers) and have a fully linked DOI wherever a DOI appears enables this.
No - there is no need to redeposit metadata. These guidelines cover how you display DOIs on your website.
When Crossref was founded in 2000 we recommended that DOIs be displayed in the format doi:10.NNNN/doisuffix and many publishers use “doi:[space][doinumber]” or “DOI: [space][doinumber]” or “DOI[space][doinumber]“. At the time that the DOI system was launched in the late 1990s it was thought that doi: would become native to browsers and automatically resolve DOIs. This never happened and it will never happen. Advantages to changing the display to a resolvable URL - even on the page the DOI itself resolves to - include the following:
A number of style guides recommend that the DOI be included in the reference as an unlinked string. We will be contacting the main style guides to request that they update their recommendations for DOIs to use the full URL form.
Originally the “dx” separated the DOI resolver from the International DOI Foundation (IDF) website but this changed a few years ago and the IDF recommends
http://doi.org as the preferred form for the domain name in DOI URLs.
We take providing the central linking infrastructure for scholarly publishing seriously. Because we form the link between publisher sites all over the web, it’s important that we do our bit to enable secure browsing from start to finish. In addition, HTTPS is now a ranking signal for Google who gives sites using HTTPS a small ranking boost.
The process of enabling HTTPS on publisher sites will be a long one and, given the number of members we have, it may a while before everyone’s made the transition. But by using HTTPS we are future-proofing scholarly linking on the web.
Some years ago we started the process of making our new services available exclusively over HTTPS. The Crossref Metadata API is HTTPS enabled, and Crossmark and our Assets CDN use HTTPS exclusively. Last year we collaborated with Wikipedia to make all of their DOI links HTTPS. We hope that we’ll start to see more of the scholarly publishing industry doing the same.