Putting a natural sign on a note

[William Marchant]

Hi all,
The following two bars of code result in the music correctly written, 
however,
I would like to place a natural symbol on the first note of the second 
bar, just to
remind folks that it is different.  I know this is not the convention, 
but I want to do it anyhow.
Is there a way?
Bill

bf4 bf bf8 bf bf bf |    b8 b b b d4 d  |