Recommend starting with doctrinal readings, before reading historical books on Mountain Warfare. The doctrine will provide the context to pull the so-what out of the historical articles. There should be plenty of reading on Afghanistan available, but I also recommend reading about mountain warfare in northern Italy during WWI.

Recommend starting with brass tacks tactics in this U.S. Marine Manual on Mountain Warfare/Operations.

http://www.marines.mil/Portals/59/MC...-35.1A%20z.pdf

There appears to be a link the Army Field Manual on Mountain Operations here:

http://www.globalsecurity.org/milita...ndex_2003.html

Very short read, very basic, but still worth looking over:

Mountain Warfare Lessons : The Soviet Afghanistan Campaign

http://www.adl.gatech.edu/research/b...MP07010802.pdf

Found the U.S. Army's 1944 Mountain Warfare Manual accidentally while looking for the current one.

https://www.ibiblio.org/hyperwar/USA...Fs/FM70-10.PDF