Category Archives: sfx link resolver

sfx link resolver

MPG e-Books Index, welcome!

Electronic books (e-books) became more common in the last year and the MPG licensed a range of e-Book collections recently, e.g. Oxford Reference Online and Olms Online. It is a pleasure to watch how users from MPG can access a growing amount of digital resources, but the administration of e-books puts a high burden on the MPG/SFX link resolver. Why? While the number of e-journals is limited (and quite stable within this limit), the e-books collection is expected to grow constantly. In fact, an analysis of the SFX knowledge base (provided by ExLibris) shows that e-books are very badly represented in it.

At the same time, some colleagues in the MPDL build up the MPG eBooks index. This catalog was released some weeks ago and is envisioned to include all electronic books available to users in the MPG. There is no need to duplicate the effort and therefore we decided not to activate e-books directly in the SFX knowledge base, but to use the eBooks catalog instead. That is how it looks like:

e-Books service in MPG/SFX
Example URL:

Clicking on the link "MPG eBooks Index" will directly link you to the homepage of the corresponding e-book. The implementation is actually quite complex, e.g. it uses OCLC’s xISBN service to improve the hit rate. Feel free to submit any thought or comment on it.

Update: We finally managed to provide a detailed documentation in our project wiki.

DOI links hurt again

Some months ago, I wrote a blog entry called “SFX and DOI: sometimes just a pain in the neck” and it paid back today. My own post helped me solving a similar problem without spending too many thoughts… thank me! 😉

More details? The issue was raised on some mailing lists first and can be described in four bullet points:

  • IEEE Xplore only provides article level linking via CrossRef/DOI,
  • users from MPG do have access to IET content via Xplore,
  • CrossRef redirects DOI links for IET content to the IET Digital Library (see,
  • but unfortunately, this is not the place where users from MPG have full text access.

Following our own instructions, we now redirect requests for full texts published on the Xplore platform only via CrossRef if the doi site key is assigned to IEEE. The downside is that only a link to the table of contents can be provided for IET content.

Example: In the MPG/SFX menu below, the link "IEEE/IEE Electronic Library" leads to the table of contents on Xplore, while the “DOI” link still resolves to the content on the IET Digital library.

Jeff Pache (IET Publishing Services & Product Development Manager) meanwhile announced that IET and IEEE will register secondary URLs pointing to Xplore at CrossRef. This is already done for some articles, see

This is a huge improvement indeed, but – from the link resolver perspective – will resolve the problem only partially. The link resolver is supposed to figure out the appropriate copy without displaying any intermediate screens to its customers. From our point of view, IEEE Xplore requires an independent article level syntax. We requested this… let’s see what happens!

Missing MPG/SFX in PubMed?

NCBI PubMed is a resource free available to everybody without any subscription or registration. Therefore, we cannot specify MPG/SFX as the default link resolver for all users from the MPG – as we do so for resources on subscription base. Anyway, entering the database via a special URL allows you to access MPG/SFX services directly from PubMed’s record pages:

If you don’t want to remember the above URL all th time, you may choose one of the following entry points which set the parameter automatically:

A note for MPG librarians: If you are providing a link to PubMed from your library’s homepage, you may want to update this as well 😉

Enabling OpenURL links in the reference section of APS PROLA

You would like to request the MPG/SFX link resolver directly from the references cited by an article published on the APS PROLA platform? This is possible, after you activated the feature by

  1. going to
  2. entering "" as your OpenURL setting and "Save"
  3. enjoying PROLA’s OpenURLs, e.g. from Phys. Rev. E 60, 3361 (1999)

OpenURLs in reference section of APS Prola

Update: Meanwhile we learned that APS PROLA intends to provide the OpenURL setting at institution level as well, but this will require some more time. Good news, anyway!

MPG-Bibliothekstagung 2008… wir haben fertig!

photo by dalantech.

Die Vorbereitung der MPG-Bibliothekstagungen war auch in den letzten Jahren bereits ziemlich arbeitssam, aber dieses Jahr haben wir wirklich ein Fleissbienchen verdient. Am Montag beginnt das XXXI. Librarian Meeting of the Max Planck Society und das vLib Projekt bringt mit:

Na, dann bleibt uns jetzt nur noch die Vorfreude auf eine interessante Tagung!

Are MPG/SFX buttons where the party is?

The vLib team works hard in the background to add MPG/SFX buttons to all the locations where they may be helpful for users from the Max Planck Society (MPG). This includes

  • results list of reference databases licensed within the MPG (e.g. the Web of Science) and MPG library catalogs (e.g. on the Aleph server),
  • eDoc – the institutional repository of the MPG,
  • reference lists published as part of journal articles (e.g. at Cambridge University Press or IEEE Xplore) as well as
  • free available resource like Wikipedia by using a small browser plugIn which interprets CoinS

An overview on MPG/SFX enabled resources is available in the vLib documentation, but we need your help for investigating further locations. Please inform us about those interfaces where you actually missing this option!

MPG/SFX becoming tiny

The MPG/SFX link resolver bases on the OpenURL standard which defines a way to transport bibliographic metadata via an HTTP request. This standard made context-sensitive linking possible and helped us to create many new services within in the digital library. On the other hand, OpenURLs tend to become very long – because information providers wish to deliver as much detail as possible – and are therefore often difficult to re-use, e.g. by copying it into the body of an e-mail.

But solutions are available for everything: A fellow developer just recently released a new service to make long URLs tiny and we integrated this service into the MPG/SFX menu. Therefore, you should now find a short URL at the bottom of each MPG/SFX menu:

tiny url in sfx menu

This URL will take you back to the MPG/SFX menu requested with the original OpenURL and we hope you will like it!

SFX and DOI: sometimes just a pain in the neck

One of the major goals of the MPG/SFX link resolver is to provide links to content licensed for the staff of the Max Planck Society. These links should lead you – the user – as close as possible to the relevant full text, e.g. by addressing the article’s abstract page. Unfortunately, not all information providers support a useful deep linking syntax and a hand full of publishers only enabled article level linking through CrossRef/DOI (see ExLibris’ target documentation). Therefore, the MPG/SFX resolver uses DOI redirects for several important information providers like Elsevier’s ScienceDirect and Nature Publishing Group.

The drawback of this solution is that DOIs sometimes resolve to another copy of the article than the requester has actually access to. The so called appropriate copy problem occurs for all kind of databases aggregating full texts from various publishers (e.g. EBSCOHost Academic Search Premier). In addition, it also happens quite often that journals move from one publisher’s platform to another and it takes some time until the CrossRef index is updated.

So what to do? While DOI links very often provide a better service, they may be misleading in rare cases. After receiving an error report from one of our users, it looks like we found a feasible solution which might be worth further exploring. The trick uses the fact that each DOI carries the information about the particular publisher responsible for resolving the target URL in its prefix (see list of doi site keys). The MPG/SFX link resolver now checks the site key to ensure that the DOI link is forwarded to the appropriate publisher for a specific target.

Anyway, some twists are possible with content moved between platforms and we are very interested in hearing about any weird experience you may have done with full text linking via MPG/SFX. So please submit a comment via the MPG/SFX feedback form whenever you are stranded far away from the full text of your interest.

Detailed background information on how MPG/SFX uses DOIs is available in the vLib project documentation.