Letter from Reichsfuehrer-SS Himmler to SS-Oberfuehrer Brack, 11 August 1942
[ToWC, Vol. I, p. 722]
It is only today that I have the opportunity of acknowledging the
receipt of your letter of June 23. I am positively interested in
seeing the sterilization by X-rays tried out at least once in one camp
in a series of experiments.