I've become enamored with The Great War recently and have a reading list set up that includes Ernst Junger's Storm of Steel and Ludendorff's Own Story by the man himself.
I'm looking for mostly primary resources but anything would be helpful.
Ring of Steel is a pretty decent addition, though the focus is not entirely on Germany. The author talks about both Germany and Austria-Hungary's motivations towards the "Ring of Steel" allies in Europe. A lot of his primary sources are first-hand via diary entries and letters, which show troop morale and reasoning for army collapse at the end of the war.
I hope this is something you're interested in.