Harmonics w/ Regular Notes

[Dave Bellows]

Hello everyone,

I'm using Lilypond 2.11.65 to create a score for guitar.  Here's the
basic snippet I'm working with:

{a4 d b} \\
{f4 g r}

I need the top line to be artificial harmonics but the lower line to
be regular noteheads.  If I write:

{\override Staff.NoteHead #'style = #'harmonic-mixed a4 d b} \\

for the top line then both lines are made into harmonics.  If I keep
that and write the second line:

{\override Staff.NoteHead #'style = #'default f4 g r}

then both lines have regular noteheads (i.e., no harmonics on either line).

I am new to Lilypond but I have spent a good bit of time trying to
figure this out.  I would appreciate any suggestions.

David Bellows