Helmholtz, Hermann von, 1821-1894
Letters of Hermann von Helmholtz to his wife, 1847-1859 / edited by Richard L. Kremer.
Helmholtz, Hermann von, 1821-1894 -- Correspondence.
Helmholtz, Olga von, 1826-1859 -- Correspondence.
Scientists -- Germany -- Correspondence.
Physiologists -- Germany -- Correspondence.
Helmholtz, Olga von, 1826-1859.
Kremer, Richard Lynn.