Jonathan Day, Robert Frank's "The Americans": The Art of Documentary Photography (Intellect Books; distributed by University of Chicago Press, 2011).
from the publisher:
In the mid-1950s, Swiss-born New Yorker Robert Frank embarked on a ten-thousand-mile road trip across America, capturing thousands of photographs of all levels of a rapidly changing society. The resultant photo book, The Americans, represents a seminal moment in both photography and in America's understanding of itself. To mark the book’s fiftieth anniversary, Jonathan Day revisits this pivotal work and contributes a thoughtful and revealing critical commentary. Though the importance of The Americans has been widely acknowledged, it still retains much of its mystery. This comprehensive analysis places it thoroughly in the context of contemporary photography, literature, music, and advertising from its own period through the present.