Apple //+ floppy technical info

[kents@fs.cei.net]

My appreciation to those who responded to my last post, and to the person who
suggested that I check my message formatting.  I brought that message up
on a different newsreader and saw how difficult it was to read.  My apologies
for that, I was using a newsreader still in Beta...guess it still has a few
minor kinks in it.
Since I have a bit of free time (and not much of a life <grin>), I'm going to
delve deeper into the old computer I have that emulates Apple and IBM.
Unfortunately, the computer can read Apple disks only when in the Apple
emulation.  However, the FORMAT utility is very powerful and very
programmable.  Any disk format can be edited, and new formats can be defined.
Where can I find technical information on the Apple // disk format?  I need
info such as read/write gap length, format gap length, format interleave, etc.
Any help will be greatly appreciated.