For further information about Military English, you can find a wide range of books in bookshops such as http://www.casadellibro.com/
CAMPAIGN ENGLISH FOR THE MILITARY 1: STUDENT's BOOK
MACMILLAN PUB. LTD., 2004
MACMILLAN HEINEMANN, 2004
CAMPAIGN ENGLISH FOR THE MILITARY 2 STUDENT'S BOOK
MACMILLAN HEINEMANN, 2009