Author: Ed Pentz

New Crossref DOI display guidelines are on the way

TL;DR

Crossref will be updating its DOI Display Guidelines within the next couple of weeks.  This is a big deal.  We last made a change in 2011 so it’s not something that happens often or that we take lightly.  In short, the changes are to drop “dx” from DOI links and to use “https:” rather than “http:”.  An example of the new best practice in displaying a Crossref DOI link is: https://doi.org/10.1629/22161

Hey Ho, “doi:” and “dx” have got to go

The updated Crossref DOI Display guidelines recommend that https://doi.org/ be used and not http://dx.doi.org/ in DOI links.  Originally the “dx” separated the DOI resolver from the International DOI Foundation (IDF) website but this has changed and the IDF has already updated its recommendations so we are bringing ours in line with theirs.

We are also recommending the use of HTTPS because it makes for more secure browsing.  When you use an HTTPS link, the connection between the person who clicks the DOI and the DOI resolver is secure.  This means it can’t be tampered with or eavesdropped on.  The DOI resolver will redirect to both HTTP and HTTPS URLs.

Timing and backwards compatibility

We are requesting all Crossref member publishers and anyone using Crossref DOIs to start following the updated guidelines as soon as possible.  But realistically we are setting a goal of six months for implementation; we realize that updating systems and websites can take time.  We at Crossref will also be updating our systems within six months – we already use HTTPS for some of our services and our new website (coming very soon!) will use HTTPS.

An important point about backwards compatibility is that “http://dx.doi.org/” and “http://doi.org/” are valid and will continue to work forever–or as long as Crossref DOIs continue to work–and we plan to be around a long time.

We need to do better

Reflecting on the 2011 update to the display guidelines it’s fair to say that we have been disappointed.  It is still much too common to see unlinked DOIs in the form doi:10.1063/1.3599050 or DOI: 10.1629/22161 or even unlinked in this form: http://dx.doi.org/10.1002/poc.3551

What’s so wrong with this approach?  To demonstrate, please click on this DOI doi:10.1063/1.3599050 – oh, you can’t click on it?  How about I send you to a real example of a publisher page.  What I’d like you to do is click the following link and then copy the DOI you find there and come back – http://dx.doi.org/10.1002/poc.3551.

Are you back? I expect you had to carefully highlight the “10.1063/1.3599050” and then do “edit”, “copy”.  That wasn’t too bad but the next step is to put the DOI into an email and send it to someone.  But wait – what are they going to do with “10.1063/1.3599050”?  It’s useless.  If you want it to be useful you’ll have to add “http://doi.org” or https://doi.org/ in the front.

When publishers follow the guidelines it makes things easier – if you go to https://doi.org/10.1063/1.3599050 you’ll note that you can just right click on the full DOI link on the page and get a full menu of options of what to do with it.  One of which is to copy the link and then you can easily paste into an email or anywhere else.

However–putting a positive spin on the spotty adherence to the 2011 update to the DOI display guidelines–everyone has another chance with the latest set of updates to make all the changes at once!

More on HTTPS (future-proofing scholarly linking)

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.

So–it’s simple–always make the DOI a full link – https://doi.org/10.1006/jmbi.1995.0238 – even when it’s on the abstract or full text page of the content that the DOI identifies – and use “https://doi.org/”.

Dr Norman Paskin

Dr Norman Paskin
Dr Norman Paskin

It was with great sadness and shock that I learned that Dr Norman Paskin had passed away unexpectedly on the 27th March. This is a big loss to the DOI, Crossref and digital information communities. Norman was the driving force behind the DOI System and was a key supporter and ally of Crossref from the start. Norman founded the International DOI Foundation in 1998 and ran it successfully until the end of 2015 when he moved to a strategic role as an Independent Board Member. Continue reading “Dr Norman Paskin”

PubMed Central Links to Publisher Full Text

A CrossRef Member Briefing is available that explains how PubMed Central (PMC) links to publisher full text, how PMC uses DOIs and how PMC should be using DOIs. The briefing is entitled “Linking to Publisher Full Text from PubMed Central” (PDF 85k).
CrossRef considers it very important the PMC uses DOIs as the main means to link to the publisher version of record for an article and we are recommending that publishers try to convince PMC to use DOIs in an automated way. Almost all of the PMC articles contain DOIs but they aren’t linked. This seems like a waste considering that publishers have invested a lot in CrossRef and DOIs as unique identifiers and persistent links.
This issue will be of interest to anyone who publishers journal articles that are the result of NIH funding and fall under the NIH Public Access Policy.

DOIs and PubMed Central – why no links?

Further to my previous post “NIH Mandate and PMCIDs” we’ve been looking into linking to articles on publishers’ sites from PubMed Central (PMC). There are a couple of ways this happens currently (see details below) but these are complicated and will lead to broken links and more difficulty for PMC and publishers in managing the links. CrossRef is going to be putting together a brieifing note for its members on this soon.
The main issue we are raising with PMC, and that we will encourage publishers to raise too, is why doesn’t PMC just automatically link DOIs? Most of the articles in PMC have DOIs so this would require very little effort from PMC and no effort from publishers and would give readers a perisistent link to the publisher’s version of an article.

Continue reading “DOIs and PubMed Central – why no links?”

NIH Mandate and PMCIDs

The NIH Public Access Policy says “When citing their NIH-funded articles in NIH applications, proposals or progress reports, authors must include the PubMed Central reference number for each article” and the FAQ provides some examples of this:
Examples:
Varmus H, Klausner R, Zerhouni E, Acharya T, Daar A, Singer P. 2003. PUBLIC HEALTH: Grand Challenges in Global Health. Science 302(5644): 398-399. PMCID: 243493
Zerhouni, EA. (2003) A New Vision for the National Institutes of Health. Journal of Biomedicine and Biotechnology (3), 159-160. PMCID: 400215
It’s interesting to note that on PMC itself both the PMCID and DOI are included – but the DOI isn’t linked. Two things occur to me – 1) should CrossRef map DOIs to PMCIDs and vice versa and make PMCIDs available in it’s query interfaces and 2) shouldn’t publishers ask that the PMC copy of the article link back to the publisher version? It would be very easy with the DOI.

BISG Paper on Identifying Digital Book Content

BISG and BIC have published a discussion paper called “The identification of digital book content” – http://www.bisg.org/docs/DigitalIdentifiers_07Jan08.pdf. The paper discusses ISBN, ISTC and DOI amongst other things and makes a series of recommendations which basically say to consider applying DOI, ISBN and ISTC to digital book content. The paper highlights in a positive way that DOI and ISBN are different but can work together (the idea of the “actionable ISBN” and aiding discovery of content). However, it doesn’t go into much depth on any of the issues or really explain how all these identifiers would work together and the critical role that metadata plays.
Nevertheless it’s great that the paper has been put forward as a discussion document – CrossRef plans to respond and be part of the ongoing discussion in this area.

Zotero and the IA

Dan Cohen at Zotero reports (Zotero and the Internet Archive Join Forces) on a very interesting tie up that will allow researchers using Zotero to deposit content in the Internet Archive and have OCR done on scanned material for free under a two year Mellon grant. Each piece of content will be given a “permanent URI that includes a time and date stamp in addition to the URL” ( would Handle or DOI add value here?) and be part of Zotero Commons (things can also be kept private within a group).
Zotero Commons is related to but different from Nature Precedings and WebCite in that it’s intended focus is on public domain stuff on researchers hard drives rather than someone else’s material or website that is cited (WebCite) or preprints, datasets, technical reports that are given at least an initial screening (Nature Precedings).

STM Innovations 2007

After a busy Online Information conference, Friday was the STM Innovations Meeting in London (presentations not online yet). There was a very nice selection of tea which helped get the morning off to a good start.
Patricia Seybold kicked off with a review of Web 2.0 that mentioned lots of sites and some good case studies:
Alexander Street Press (http://www.alexanderst.com/) – user tags combined with a taxonomy.
Slideshare (http://www.slideshare.net) – share presentations
Threadless (http://www.threadless.com/) – design and vote on t-shirts
The most interesting parts of the talk were the case studies of how National Instruments and Staples have built a vibrant community of customers. Staples invited top purchasers on the their site to create product categories and sales went up 30% and now they use the categorization in physical stores and customer reviews from the web are used in stores.

Continue reading “STM Innovations 2007”

ACAP – Any chance of success?

ACAP has released some documents outlining the use cases they will be testing and some proposed changes to the Robots Exclusion Protocol (REP) – both robots.txt and META tags. There are some very practical proposals here to improve search engine indexing. However, the only search engine publicly participating in the project is http://www.exalead.com/ (which according to Alexa attracted 0.0043% of global internet visits over the last three months). The main docs are “ACAP pilot Summary use cases being tested”, “ACAP Technical Framework – Robots Exclusion Protocol – strawman proposals Part 1”, “ACAP Technical Framework – Robots Exclusion Protocol – strawman proposals Part 2”, “ACAP Technical Framework – Usage Definitions – draft for pilot testing”.
What would cause other search engines to recognize the ACAP protocols rather than ignore them? A lot of publishers implementing this and requiring search engines to recognize it to index content could put pressure on the engines. Maybe.