D O C U M E N T 4 5 4 – 4 5 6 M A R C H 1 9 2 3 3 8 3 454. To Heinrich Lüders Berlin, 24 March 1923 Esteemed Secretary, With reference to your esteemed letter of the 15th of Feb. of this yr.,[1] I take the liberty of informing you of the following. When my appointment to our Academy was being envisioned in 1913, my colleague Haber called my attention to the fact that my appointment would have the consequence that I would become a citizen of the Prussian State. Because I considered it important that absolutely nothing change with regard to my citizenship, I made my acceptance of an eventual appointment conditional upon satisfaction of this provision, which was then also granted accordingly.[2] I do not doubt that this matter can be verified in the minis- terial files furthermore, I know that this situation is known to my colleagues Haber and Nernst.[3] In great respect, A. Einstein. 455. To Sergei F. von Oldenburg Berlin, 24 March 1923 Highly esteemed Colleague, I happily and thankfully accept the election as corresponding member of your Academy.[1] I followed with admiration how, with so much love and success, sci- entific research was kept alive in your severely tested country. In utmost respect, A. Einstein. 456. From Paul Ehrenfest [Leiden,] 27 March 1923 Dear Einstein First of all, cord. greetings on your return back home from the exotic world.[1] — I am sorry to hear that your wife isn’t well. Give her my sincere regards—a speedy recovery!