2 Titel in Gauss, William Theodore

• 

  Brief an Mr. [Erich] Bessel-Hagen

  Gauss, William Theodore ; Bessel-Hagen, Erich

  Colorado Springs, Colo., 09.11.1927 [Nov. 9th 1927]
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  Brief an Mr. Hagen [Erich Bessel-Hagen]

  Gauss, William Theodore ; Bessel-Hagen, Erich

  Colorado Springs, Colo., 16.03.1927 [March 16th 1927]