Welcome Preppers and Survivalists,
孫子(ca 544 – 496 BC)
Several weeks ago, Ol' Remus, over at Yer Ol' Woodpile Report, linked to an article titled Lessons From the Roman Art of War. In the article, the writers provide some advice from Epitoma Rei Militaris by Publius Flavius Vegetius Renatus.
The book, translated title, Epitome of Military Science was written around 450 A.D. According to an on-line retailer, a 1996 english translation version will set you back anywhere from $300 to $630 depending on your choice of 'new' or 'used.'
Of course, I don't have that kind of money, so I went looking for a
Digital Attic - The Military Institutions of the Romans (De Re Militari)
Yes, I know that Wikipedia is a poor source for research, but (I believe) it's a good starting point on doing basic research that will lead me (you and your family) to better quality sources.
With that said, there is some concerns about Vegetius' work, a thousand years later, as other authors' and historians' classic works were found and translated.
As all students know, times change and other information becomes available to explain the ways the world works, some simple and some complex.
One simple text, about warfare, that you might be interested in is a book by Sun Tzu titled The Art of War.
Digital Attic - Warfare