Is there reference manual for sh?

[a at zeos.net]

On Sat, Dec 30, 2006 at 10:16:20AM -0500, Robert Huff wrote:
> 
> a at zeos.net writes:
> 
> >  I need a reference manual or specification for sh.
> >  Where can I find it?
> 
> 	In you mean within FreeBSD, try:
> 
> 	man sh
> 
> 	or
> 
> 	man builtin,
> 
> 	As a user, the O'Reilly _UNIX in a Nutshell_ I bought many
> years ago was a very wise investment.
> 	If you want to hack the code ... the start with the code.  And
> good luck.
> 
> 
> 				Robert Huff

I need any online complete manual on sh, not a brief as it is man sh.
The last one doesn't describe many features both interactive (command line 
editing, using history interactively, and many others) 
and scripting (for example, conditional expressions).