US Army Regulation 25-50

The Army Regulation (AR) 25-50 Preparing and Managing Correspondence is the United States Army's administrative regulation that "establishes three forms of correspondence authorized for use within the Army: a letter, a memorandum, and a message."
Style Manuals.
APD uses the following references and style manuals: 
Microsoft Word Templates.
APD prepared templates for use in Microsoft Word 97 for members of the Department of the Army.
There are a number of other templates and documents purporting to be templates on the Army's milSuite collaboration site. This page provides a scaffolding for other users to publish Microsoft Word templates.