Image float

Hello,
I've been searching about how to make an image float, so the text is next to 
the image and I didn't find anything useful .
I need to export to PDF using XSL and FOP:
xsltproc --output 
documentacion.fo /usr/share/xml/docbook/stylesheet/nwalsh/fo/docbook.xsl 
doc.xml && fop doc.fo doc.pdf

I'm not able to get this effect. This was a surprise as it's a very common 
layout.

Thank you.

-- 
Adrián Ribao Martínez