BibTeX, biblatex and biber ⇒ abbrvnat style problem with citation

[may]

Hey,

I'm writting my thesis and have a problem using the abbrvnat style. If I have more than 3 authors the style makes automatically author1 et al but afterwards still lists the other authors. For example:

[Carrizosa et al.(1995)Carrizosa, Conde, Fernandez, and Puerto] E. Carrizosa,
E. Conde, F. Fernandez, and J. Puerto. Multi-criteria analysis with partial
information about the weighting coefficients. European Journal of Operational
Research, (81):291–301, 1995.

I want to have only:

[Carrizosa et al.(1995)]

I use BibDesk and already found a guy who had the same problem and changed the brackets, i.e. instead of { he made " what solves his problem but it doesn't work for me...

can somebody help me?

Thanks!