Gustav Hertz Signed Photo (Back) + Envelope Nobel Prize Physics Autographed RARE

Description

Rare Gustav Hertz 4" x 5.5" photo, signed on the back. Also included is the original mailing envelope, with Dr. Hertz's return address printed on back. There are four small tape stains along the edges of the back of the photo (see third image), otherwise the photo and signature are in excellent condition.
I guarantee the authenticity of this autograph. If it fails to pass authentication at any time, return it for a full refund, including your shipping costs. I've been buying and selling autographs for 30 years, I was a feature writer for Autograph Collector Magazine in the 1990, and I've been selling on Ebay since 2001.
Please see my extensive autograph listings - I'm happy to combine shipping. Thanks, and happy collecting!