[NTG-context] How to use utopia font?

hello all, I'm new with ConTeXt even if I know some TeX and LaTeX already. Here is my question: I would like to use utopia (with expert fonts) as my default rm. I've got all the files required for a LaTeX usage (with fourier.sty) and it works ok. I have found some fourier.map and fourier-utopia-expert.map in my TeXlive under /texmf-dist/fonts/map/dvipdfm/context and /texmf-dist/fonts/map/fourier/. I've tried what I've understood of the manuals but I can't figure out how to call correctly the font. Any hint will be appreciated. Thanks to all -- Yvon Henel