[Plugin: WP About Author] double author

Hi,
I ca see in the post page of my blog two author description. one is the User I stetted up on wordpress and the other one is the one made with wp-about-author .
Is there any way I can only keep the wp-about-author ?
Thanks

Here is a sample
http://www.viaggiare-low-cost.it/viaggiare-low-cost-2/viaggiare-da-soli-per-lunghi-periodi-pro-e-contro/

Giulia

http://ww.wp.xz.cn/extend/plugins/wp-about-author/