Einstein, Albert, 1879-1955
W. Rn̲tgen, M. Planck, and A. Einstein letters regarding Siemens prize, 1916.
Photocopies of letters from W. Rn̲tgen, M. Planck, and A. Einstein.
Siemens Prize.
Planck, Max, 1858-1947.
Rn̲tgen, Wilhelm Conrad, 1845-1923
AIP-ICOS
American Institute of Physics. Niels Bohr Library & Archives. One Physics Ellipse, College Park, MD 20740, USA