Apocalypse reading is big nowadays. It is a staple of modern existence. We always think the worst is around the corner. And personally, I think so too. So, it is best to stay prepared. Lists of essential survival items can be found aplenty online. Just Google them. What about essential list of books that might guide us through various post-apocalyptic survival situations? io9.com has such as list on outdoor survival, food, medical care, shelter,  homesteading, and rebuilding civilization. . A quick list of 18 books they have listed:

General Survival and Homesteading:
1. SAS Survival Handbook
2. US Army Field Survival
3. Foxfire Books
4. The Encyclopedia of Country Living by Carla Emery
5. Back to Basics: A Complete Guide to Traditional Skills by Abigail R. Gehring

Medicine:
(apart from free information from WHO)

6. Where There is No Doctor
7. Ditch Medicine : Advanced Field Procedures for Emergencies by Hugh L. Coffee
8. A Field Guide to Medicinal Plants and Herbs: Of Eastern and Central North America (Peterson Field Guide)

Food:

9. Peterson Field Guides to Edible Wild Plants
10. The New Self-Sufficient Gardener by John Seymour
11. Root Cellaring: Natural Cold Storage of Fruits & Vegetables by Mike and Nancy Bubel
12. The Trapper's Bible: Traps, Snares & Pathguards by Dale Martin
13. A Guide to Canning, Freezing, Curing & Smoking Meat, Fish & Game by Wilbur F. Easton

Shelter:
14. Shelters, Shacks, and Shanties: The Classic Guide to Building Wilderness Shelters by D. C. Beard
15. The Building Blocks to Rebuild Civilization: The CD3WD project 

You should the complete post at io9.com for more tips from commenters as well.

 + My tips: Download the Wikipedia - English version | Search Google for free guides from U.S. Military, U.S. Special forces, United Nations-related organmizations, etc.

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