Double notes

[James Wilkinson]

Hi there.

I've been using Lilypond for a while, but there's one thing I can't get to 
work.

I have two voices on a stave. Call the voices soprano and alto (I'm
writing sheet music for a four part choir). If the soprano and alto are
both singing a minim (half-note) G (for example), then you correctly get
one head, with one stem going up, and one stem tail going down. (Always
assuming that you use \stemUp and \stemDown.

However, when they both sing a semibreve (whole note) C, there are 
obviously no stems. In "normal" printed music, you have *two* C 
semibreves, touching, both on the C (ledger) line.

How do I get this effect in Lilypond?

Thanks in advance,

James.

-- 
James Wilkinson       Home: address@hidden
For every complex problem, there is a solution that is simple, neat, and
wrong.