His letter accepting the rectorship of Freiburg. A first edition of the speech he gave when he accepted the position--the one where he famously says that a university must find its own identity and essence in order to adequately support the Nazi state. The letter where he resigns his position the next year. A heil Hitler signature. And, most interestingly, the academic garments he continued to wear at formal functions, signifying his position in the philosophy department, even long after he was removed from teaching after the war.A few years after being removed he was reinstated, as Emeritus. I expect pensions and such were the main issue.