Adding ezproxy to the url – 5 different methods

Many libraries in the world provide remote access to electronic resources via EZproxy .

As Andrew Perry explains here

“Essentially, Ezproxy uses some URL mangling, rewriting all hyperlinks, to pass traffic via the proxy (rather than using a conventional browser proxy setting). If the user is not logged in to the proxy (ie has no fresh & valid cookie), a login screen is given before being forwarded to the journal site.”

In the case of NUS Libraries, a user visiting will not be able to logged in via NUS Libraries and hence cannot access full text. However if he accesses the same link with the extra string in red appended , he will be accessing the page via NUS Libraries and hence will have full text access.

While links from our library portal will typically have being specially treated to include the string in red, in today’s world, a user is more than likely to stumble upon a journal vendor site from some outside source that did not rewrite the link (e.g. Blogs, forums, web search engine results). As a result, users will not be able to access the full-text article.

This is particularly so for users using Google or Google scholar. Ideally if everyone was linking using openurl (which google scholar does) and every library had a openurl resolver (not all have) things would be a lot easier (besides being a much superior method for being certain whether a library has access if the same article can be found in different sources/vendor platforms) but ….. In any case, this post assumes that linking via Openurl has not occured and one is dealing with a simple link to a specific vendor url.

In such cases, one can always manually add the string “” to the url just after the domain name but clever librarians have come up with many ingenous ways to speed things up.

Some methods that can be used include

1. Bookmarklet
2. Libx
3. Greasemonkey
4. Zotero
5 Others

Use of bookmarklet

This is perhaps the most commonly used method. For this to work, one installs a bookmarklet into the browser. Clicking on the bookmarklet will automatically append the needed ezproxy portion of the url into whatever url the user is on, hence allowing him to access the resource.

Example : NUS Library bookmarklet


Lightweight, works on most browsers.


The bookmarklet can only work retrospectively, after the user is already on the url. In most cases, as the user is initially not authenticated via EZproxy, the page shown will be the public page. Clicking on the bookmarklet will then convert the page into the subscribed version. Unfortunately, some vendors will detect that you are not authorized to access the page and redirect the page to a generic error page. Obviously, clicking on the bookmarklet now, would be futile. Vendors that do this include Web of Science and Scopus?.

Also certain vendor sites (Wiley-blackwell is one) will report errors with cookies, when using the bookmarklet. The only way around these problems would be to convert the url on the fly before even hitting the page (Which the Greasemonkey script, Libx and Zotero do).

Libx toolbar

As I covered in a past post , Libx toolbar is a specialized custom toolbar that libraries can offer to their users to help enhance access to their collections. Among the many functions of Libx is the ability to support the use of EZproxy. This is done via two methods

1. When the user is already on the page.

Similar to the bookmarklet method, when the user is on a page that he is unable to access, he can right click and select the option “Reload via Library proxy”, and this will automatically reload the page he is on, with the ezproxy built in.

2. Prior to visiting the page.

Alternatively, before even hitting the page, he can right click on the link and select “go to via Library proxy”. This can be helpful in avoiding the situation mentioned above with vendors redirecting to generic error pages.

Example : NUS Libx toolbar demo


Because one can rewrite the url link , before even visting the url, this avoids the problem mentioned above with vendors redirecting to generic error pages. Also Libx supports both main browsers Firefox and Internet Explorer, although the bookmarklet supports more browsers.


Libx adds a ton of features, and is probably overkill, if all you want is just some way to add support to exproxy. It is of course possible to create a small simple Firefox addon that does just these functions, for instance recently I discovered this from way back in 2005!

Using Greasemonkey script
Greasemonkey is a Firefox addon that allows users to dynamically rewrite webpages. It is possible to create a greasemonkey script that will on selected domains (which user can add) rewrite outgoing urls to work with ezproxy.

Example : Greasemonkey script demo (NUS libraries) , Script originally from Andrew Perry


Unlike using bookmarklets or Libx, once configured properly, outgoing links will be automatically rewritten. Users save time, because they don’t have to click on the bookmarklet or right click and select context menu etc for it to work everytime you go to Jstor via Google scholar. You can also add more domains into the list.


Greasemonkey is Firefox only, though Internet explorer users might try it with greasemonkey with IE.

Once a domain is added, all outgoing links will be converted. This can cause problems in some instances. For example, one can’t simply add* and hope to convert all Google scholar links, because the next page button doesn’t work then!


Zotero is a well known opensource citation manager that runs as a Firefox add-on. It has tons of powerful features. However the latest 1.5 beta adds automatic proxy support

When I first read about it, I thought it worked like Libx‘s. But I was wrong, it’s far cleverer.

It works as follows, the first time you visit any url via ezproxy, Zotero will popup the following dialog box.

There isn’t much detail on how it works. But here’s my understanding, if you click “add proxy”, Zotero will silently track any urls that use ezproxy, and automatically create pattern matching rules so that similar urls to the same domain will be converted as well.

For instance if you visit for the first time, Zotero will notice that you are using a proxy to access If you click “Add proxy”, two things will happen

1) In the future whenever you go to any link that has in it, will be automatically appended.

2) In addition, you are not just restricted to Springer. if you next visit say JSTOR at , Zotero will silently learn (no prompt) about JSTOR links as well, so again in the future similar links to JSTOR urls will be converted.
The more vendor sites you visit via ezproxy, the more Zotero learns about which links (based on domain) should be converted. All this works transparently, the user does not need to do any work at all!

In short, what you have here is a simple autolearning system, that automatically learns what urls should be converted and appends the needed string!


Very user friendly. Domains that should be converted to use with ezproxy are automatically added without intervention by user. Once Zotero has learnt that certain url from a domain should be passed through Ezproxy, it will work automatically, saving time compared to using bookmarklets or Libx.

Do note that Zotero proactively converts recognized urls similarly to greasemonkey, so it works fine with links to Web of Science or Wiley unlike using bookmarklets. Unlike greasemonkey script it selectively converts only recognized urls, rather than all urls on the page, so it works great with say Google scholar and there is less chance of problems.


Unfortunately, Zotero is Firefox only add-on, so users using other browsers are out of luck.

Also though Zotero automatically recognises urls that require the ezproxy string to be added, it does not itself add the ezproxy string when you first visit a domain it doesn’t recognize.

One can of course combine methods. Use any of the earlier methods to append the ezproxy string to any new domains not yet recognized by Zotero, and the next time when you visit links in those domains, Zotero will kick in and work automatically.

In particular, given that both Zotero and Libx are opensource tools that are popular with users of Firefox, many librarians have began to recommend the use of both . So use the later to append the ezproxy string to unrecognized domains for Zotero to learn.


These are only some methods that can be used to append the ezproxy string. No doubt there are some other methods (e.g. other Firefox add-ons such as redirector and quieturl). Update 21/4/09 : The 5th method is courtesy of a library user from my institution. He uses shortcut typing tools and recommends the following typinator, textexpander (os x); fastfox, phrase express (pc).  These tools allow you to type a letter or two and expand it into a whole phrase, like a macro.

Overall I think Zotero‘s method is the smartest and easiest way to solve the problem of automatically adding the ezproxy string. It might even be worth installing it alone for this feature, if you constantly find yourself needing this feature.

Do note that if you append the ezproxy string and you still don’t have access, it doesn’t necessarily mean your library does not have access to that article. It is possible that you can still access the same article via another vendor or site.

Rss feeds, Library databases and yahoopipes

This post will discuss how to use RSS feeds from library databases. It’s surprisingly tricky to do it compared to subscribing to normal RSS feeds from most blogs. This is due to the fact libraries generally provide access via a proxy – ezproxy to provide remote access to databases off campus.

As most readers of this blog are probably reading this off a RSS feed, I won’t explain what a RSS feed is. If you have no idea what it is, please consult this guide.

The basic idea is this, do a search on a library database, create a RSS feed of the results and put it into your favourite feed reader (Google reader, Bloglines, FirefoxInternet explorer 7 , Outlook 2007 etc), After which you can watch new results come in as and when the database is updated in it without needing to run the search again or visit the database site again.

Some library databases that provides results and alerts vis RSS include ScienceDirect (via NUS Libraries), Scopus (via NUS Libraries), Engineering Village (via NUS Libraries) databases on ProQuest (e.g. ABI/Inform via NUS Libraries),  Ebscohost (e.g. Business Source premier via NUS Libraries) , OVIDSP (e.g. EconLit via NUS Libraries) etc.  How you get the rss feed url differs but generally you click on the RSS button that appears on the results page (see below for example from Engineering Village)

However, if you try to just stick the url given by the database directly into your feed reader (see image below) you will be doomed for disappointment, it doesn’t work!

The technical reason and solution for this can be found here .

However for now there’s a work-around.

The method describes below is specific to databases subscribed via NUS Libraries, but any library (e.g. NTU, NLB) using ezproxy to provide remote access should be able to do something similar by removing the particular proxy stem.

You need to delete the part that says “” before pasting the url into your feed reader.

NLB users should remove “” , while NTU users should remove “

Most guides I have seen on library webpages stop here. While this works, and the results will be pulled into your RSS feed reader (see below), you will be disappointed when you click on the link in the feed reader.

Because the rss feed url you enter lacks the  ezproxy proxy stem, the outgoing links you are sent lack it as well, and when you click on the link, it brings you to an unsubscribed version (where you can’t see the full-text) of the page at best, or at worse you get an error page (see below).

One way to solve this problem would be to add the proxy bookmarklet here to your browser (specific to NUS Libraries, NTU version is here ) and then clicking on the bookmarklet will log you in from the error page above.

But that gets tiresome as you will have to do the same for each link you click from the RSS feed.

A smarter method would be to modify the RSS feed you get to automatically append the proxy stem, (for NUS Libraries, for other libraries edit the yahoopipes accordingly) to outgoing links. This can be done via a simple Yahoopipes filter (you will need to make very minor modifications if you are from some other libraries).

1. Go to

2. Enter the rss feed url (the one that does not have the string

3. Click “run pipe”

4. On the resulting page, click on “Get as RSS” and on the resulting page, copy and paste the url into your feed reader.

5. You will find that this time, the resulting rss feed will have links that work properly now. It goes without saying that if you haven’t logged in this browser session yet, it will prompt you to  log-in first.

Some libraries discourage the use of RSS feeds because they worry the constant polling for updates will cause unnecessary number of accesses. The method described above avoids this problem.

As results are pulled into your Feed reader, there is no access via the institution library, Until you click on the link to gain access to the database,  the vendor doesn’t count it has an access from you.

I might do a post about ezproxy, and other creative uses of Yahoopipes in the future.

Until later

Aaron Tay

Google Books tips and tricks by a librarian

One visitor to my blog, commented that she couldn’t make heads or tails of my postings because it was too technical and obscure (opensearch plugins??).

To remedy that, I’m going to post some ” beginner” level posts that should be accessible to everyone. I’m going to post a series of research tips that might be helpful to less experienced users

Google books

Did you know that Google has digitalized and scanned in full-text of over 7 million books (they recently added magazines) through a service called Google books? You might in fact, come across links to Google books results while searching regular Google or Google scholar, but I personally prefer to search Google books direct if I am looking for a book.

Why you should use Google books.

Our library catalogue search (LINC) is great, but our library records contain only metadata relating to books. By metadata, I mean for each book, our library records contain summary information of the book (technical term here is surrogate record). This typically includes title, author, subject, isbn, short summaries and occasionally table of contents. Below shows a typical record in the catalogue (this time with table of contents).

All this is great, but what if the information you are searching for is in a short paragraph extract that isn’t in any of those places? Then your search will miss it! This is where Google books shines, it has scanned in every word of each book and all of it is search-able!

As long as the term you searched  for appears in the book, Google books will find it!

Why Google book can’t replace the library

As you might expect, while Google books will allow you to find books where your searched terms appears in, in most cases it will not allow you to actually read the whole book when you click on the link. There are in fact 3 scenarios (a 4th scenario is where there is just a bibliography) when you click on the link.

1. Full view

Occasionally, you will be able to see the full text of the book. This occurs typically for very old books that are in public domain and are out of copyright or in rare cases where the publisher has allowed Google books to display the whole text. You can also download the whole book as pdf.

2. Limited Preview

In most cases, publishers have allowed Google to display only parts of the book, so you will only be able to view parts of the book (pages might be missing) , and also to a maximum of X number of pages  , where X is set by the publisher.

Below shows a book with limited preview, pages 543-544 are omitted from display.

3. Snipplet view

Certain books are viewable only in snipplet view, you can only see a few lines of text, sufficient to see your search terms in context. See below.

How to use Google Books creatively

My experience is that most books you want will not be in “full view” but rather in “Limited Preview”. Despite these limitations Google books can be a powerful search tool. Here’s how you can use it to your advantage.

#1 Preview the book first to see if you want it, before coming down to borrow it.

Use Google books to quickly see if the book is worth borrowing (read sample chapters, do a search within text to see if the results look interesting etc) in the comfort of your home before coming down to the library to borrow it.

# 2 Read

portions of the book if item is  checked out.

Looking for a RBR book or a popular book that is checked out and you need it desperately?  You can place a hold, but what do you do in the meantime? If you are looking only for a chapter , you might get lucky and Google books in limited preview might allow you to  read the whole chapter. If not, reading parts of it, might be better than nothing until you finally get the book.

#3 Harness the power of full-text search to find items that you might have missed otherwise (general).

If your search terms are not getting many results in the library catalog, try searching in Google books. You will get more results for sure, because Google books will match books as long as the terms appears anywhere in the text and not just in the title, author, subject or summaries for Library catalogue searches.

Typically the most relevant results that appear in Google books, but not in the catalogue search will be chapter titles. Sadly while some of our catalogue records incorporate table of contents, not all of them do yet.

I also find this feature particularly useful for searching for very obscure and rare terms that don’t merit a whole book or even chapter written on it.

#4 Finding specific statistics

Looking for some obscure piece of statistic? I have found that Google book search is perfect for hunting for obscure statistics. Typically all you need is just the table or chart, so you don’t want or need to read the whole book anyway. Try searching for example food subsidy as percentage of gdp in India. We have many of the books listed in our library, but why borrow the whole book, when all you need is just one page?

You could of course just do a normal google web search, but then you would have to spend time figuring out if the website you found it is reliable or not (Warning! books are generally more reliable than any random website if they have gone through editorial review and control, but not all books are equally creditable!)

#5  Finding book citations and biographies

Want to see which books cited or mentioned a journal article or book you are interested in? Do a search in Google books and compare the results when you search for an article name in quotes in Google books with the cited reference search of the same article in Scopus. See the difference?

#6  Finding a book whose title you can’t recall.

Trying vainly to recall the title of a book you have read or borrowed in the past, and you haven’t had the foresight to turn on our my reading history feature . If you can remember some of the more unique words in the book , the year etc, Google books (advanced search) might help. Trying adding as much information as you can to narrow it down as much as possible.

#7 Downloading full-text of older books in pdf

If you are a history buff, you are in luck! Many of the oldest texts are obviously in public domain now, and are available in full view mode. You can view and download the whole item in pdf. Take a look at the following item which is in our rare book collection , but you can download the full text in pdf here . If you just want to look at books available in full view mode, use the advanced search to restrict searches to books with only full view.

#8 Search Google books with Android and iPhone

For Android and iPhone users you can now use Google books at the mobile site here !

#9 Learn to use the advanced search features of Google scholar to limit the search

Given that google books searches every word in every text out there, if you are not careful you are going to get thousands of hits. Google Books tries to rank what it considers most relevant at the top, but it is helpful if you know how to restrict searches  to get exactly what you need. There are many wonderful guides out there (e.g here and here) on this so I won’t elaborate  further.

#10 Secret tip

Every tip and tricks page needs to end in a round of 10. This last secret tip I discovered by accident. I will only reveal it if there are more than 5 real,sensible comments (I get to decide what counts) from 5 different users.  But I seriously doubt it will happen.

Until next time.

Aaron Tay

A Comparative Citation Analysis of Web of Science, Scopus, and Google Scholar (article review)


Levine-Clark, M., & Gil, E. L. (2009).
A comparative citation analysis of web of science, scopus, and google scholar.
Journal of Journal of Business and Finance Librarianship, 14(1), 32-46.
Read full text


There are numerous articles comparing the big 3 cross-disciplinary databases, namely Web of Science,
Scopus and Google scholar. The article above is yet another one written on the same topic. It dutifully
covers old ground by explaining that ISI’s Web of Science is the oldest of the three, with the most depth
(it has the oldest archives) but the least breadth (because it indexes only the most prestigious journals).
Google scholar on the other end of the spectrum is the broadest of the three but mixes in results from
unofficial sources. Scopus lies somewhere in between. It dutifully explains reasons for why citation counts for an article tend to increase as you move from Web of Science to Scopus to Google Scholar. Bauer and Bakkalbasi (2005)‘s often mentioned recommendation that one combine either Scopus or Web of Science
with Google Scholar is mentioned again.


Somewhat uniquely the sample articles used for this study comes from business/economics journal set.
They use ISI as a base to select the top 5 ISI and bottom 5 ISI journals based on Impact factors.
In addition they randomly select another 5 Journals not on ISI from Scopus.

For each of 15 journals, they do the following.

  1. Use Sciencedirect’s Top 25 hottest article feature to select 25 “hottest articles”
  2. Any other articles in the same journal issue as the selected 25 “hottest articles” are also selected and are termed “unranked articles”
  3. The total number of citations are then searched for in Web of Science , Scopus and Google scholar.

Major findings

The results are hardly surprising really. As expected

  1. Citations increase in this order, Web of Science, Scopus, Google scholar
  2. Articles from top 5 ISI Journals have higher average citation than those from bottom 5 ISI Journals in all 3 databases.
  3. “Hottest articles” have more average citations than “unranked articles ” across all 3 databases, showing that increased usage leads to more citations
  4. For Scopus and Web of science, Top 5 ISI Journals are compared with bottom 5 ISI Journals and Non-ISI Journals. Somewhat surprising for both, while the highest average citations came from the Top 5 ISI Journals as expected, unranked ISI Journals had higher average citiations than the bottom 5 ISI journals.
  5. For google scholar, they are found a strong correlation between the number of citations each article got and the number of hits/links to the article.