Powerful photographs helped change the tide of the Civil Rights Movement of the 1950s and 60s. Some of these very photos moved author Elizabeth Partridge (goddaughter of the influential photographer Dorothea Lange) when she saw them 40 years later. Consider the role that photographs, books, and interviews play in historical research as Partridge discusses her process of selecting viable sources for Marching for Freedom: Walk Together Children and Don't You Grow Weary (Penguin, 2009).