(See how I did that three-word compound adjective there?)
I happen to own a copy of the US government’s official style guide, the USGPO Style Guide. It’s pretty good, and if you write, and can afford a copy, I recommend it. It’s called the US Government Publishing Office Style Manual, and you can download a pdf of it, but I recommend buying a copy from Amazon or any of a couple other sources, including the US Government Printing Office. Google it.
All that to mention that the NSA of all places also has a style guide of sorts, and you can find info about it here. This is a link to a post that mentions several related grammar guides and such belonging to the NSA.
Check it out.