Places to find HEMA (Historical European Martial Arts) material
Websites:
https://www.wiktenauer.com/wiki/Johannes_Liechtenauer
https://wiktenauer.com/wiki/Joachim_Meyer
https://wiktenauer.com/wiki/Pseudo-Peter_von_Danzig
Guides
Books:
In Saint George’s Name by Christian Tobler
Fighting With the German Longsword by Christian Tobler
The Art of Combat by Joachim Meyer
Sword Fighting: An Introduction to Handling a Longsword by Herbert Schmidt
Black Bear Historical Fencing 