cello harmonics

[Richard Lyons]

I am new to lilypond (which looks really nice btw).

My first task is a cello solo.  Has many harmonics, but I think there is 
no way to enter them in lilypond.  I've looked on the archive and only 
found reference to the diamond head notation.  Is there no way to enter 
the small circle over the note for harmonics?  

Also, can the roman numerals under the note to indicate which string be 
easily produced? 

-- 
richard