Image: Salk Thank You
Description: Photo: shopkeeper expresses a nation's gratitude for Dr. Salk's discovery.
Title: Salk Thank You
Credit: March of Dimes Birth Defects Foundation; in book: Smith, Jane S. (1990). Patenting the Sun: Polio and The Salk Vaccine. New York: William Morrow. ISBN 0688094945.
Author: March of Dimes Birth Defects Foundation
Usage Terms: Public domain
License: Public domain
Attribution Required?: No