[Radiant] Best way to refer to a stylesheet?

[John and Catherine Allen]

This has to be a really basic question, but despite reading the 
documentation and many mailing list posts, I still don't get it...

For stylesheets which are stored in the database
1) In a layout, what is the recommended way to refer to a stylesheet ?
2) In a page, what is the recommended way to refer to a stylesheet ?

My stylesheets work fine when I refer to them as files in the 
filesystem, but not when they are in the database.

John

-- 
John Allen
Bofferdange, Luxembourg
allen at vo.lu
http://allenlux.dyndns.org