The basic principles of survival have been out there for some time. One of my favorite references is [/u]The Survival Book[u], by Nesbitt, Allen, and Pond. Published in 1959, it is replete with examples from WWII that are still instructive today.
While the principles endure, some of the technology has advanced - GPS, LED lights, Avalanche beacons, new synthetic clothing. The section on signal mirrors is basically current, and they cite several successful uses of the mirror in achieving rescue.
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Geezer in Chief