Podcasts:

https://www.dancarlin.com/product/hardcore-history-wrath-of-the-khans-series/

Books:

https://www.amazon.com/Genghis-Khan-Making-Modern-World/dp/1491513705

https://books.google.com/books?ei=7GQzTv7dFNPTgAe1mdzrDA&ct=result&id=6GMFAAAAMAAJ&dq=battle+of+mohi+chinese+gunpowder&q=gunpowder+mohi

Links:

http://www.historynet.com/mongol-invasions-battle-of-liegnitz.htm

http://www.atarn.org/mongolian/mn_nat_arch/mn_nat_arch.htm

http://afe.easia.columbia.edu/mongols/conquests/khans_horses.pdf

War Tactics:

https://en.wikipedia.org/wiki/Mongol_military_tactics_and_organization

http://www.alanculler.com/Genghis Khan.pdf