Reference managers are those esoteric instruments that collect references for you from the web and allow you to insert them in your text documents. In addition, they allow you to create a reference list at the end of your document, sorting by First Author’s name or by order of citation. They also allow you to decide if in a paper with 283 authors you really want to list ’em all or if you are heppy with just 5 (or 10) of them.
In the last few years I probably tried most of the available reference managers, and after some degree of scientific experimentation I can ensure you: reference managers are great! And some of them are also available free of charge.
Among free reference managers two are probably the most widely used: zotero (http://www.zotero.org/) and Mendeley (http://www.mendeley.com/).
Ok. That was the up side. What about the down side?
If you are a scientist and you submitted your work to different journals, you probably know how good they are in requiring slight deviations from widely established citation formats. going back to the example of the number of auhtors, some want you to cite all the authors of a paper, some want only the first one, followed by et. al, some want only the first 5, or 7, or 10 or … AAAAAARRRGHHHH!!! I will never find the right style for the journal I want to submit to! Actually, the number of journals for which a style is available is pretty high (more than 1500, as of today) but Murhpy’s law is there to ensure your journal will be missing. But don’t panic. It is not so difficult to create your own style.
I did it, and it worked.
Citation styles for both zotero and Mendeley are written in .csl (citation style language) an esoteric language which I heard is similar to .xml. Given the large number of styles availalbe, you just have to find a style similar to what you need and then modify the .csl file according to the requirements of the journal.
A nice tutorial on how to modify existing styles is on the zotero forum:
http://www.zotero.org/support/dev/citation_styles
There you will also find links to primers to csl, and instructions on how to submit your style to the zotero community. Submitting your style to zotero also ensures it will be available in mendeley quite soon.
However, you can also just add your style in Mendeley.
To use it in Mendeley, just copy the my-new-style.csl file in the Mendeley Desktop styles directory (usually citationStyles-1.0).
In your word processing software select “choose citation style”, then “more styles” and your newly created my-new-style will be among the installed styles, you just have to select “use this style”.
Fabio Marroni's Blog 
Hi Fabio, great post. In fact, CSL is very similar to XML and not that difficult to get into. More so, I’d like to point you to a blog post we have on the Mendeley blog showing how to edit citation styles. There’s even a short video toward the end: http://www.mendeley.com/blog/research-tutorials/howto-edit-citation-styles-for-use-in-mendeley/ Let me know what you think about it.
Disclaimer: I’m a community liaison at Mendeley 🙂
Hi Ricardo,
I think the video is great! It summarizes in 2 minutes most of the info you need to create a style!
I agree that csl is not that difficult, although I heavily relied on http://citationstyles.org for help!!!