Horan, J. D. (1966). Timothy O'Sullivan, America's forgotten photographer; the life and work of the brilliant photographer whose camera recorded the American scene from the battlefields of the Civilo War to the frontiers of the West. Doubleday.

Horan, James David. Timothy O'Sullivan, America's Forgotten Photographer; the Life and Work of the Brilliant Photographer Whose Camera Recorded the American Scene from the Battlefields of the Civilo War to the Frontiers of the West. Garden City, N.Y: Doubleday, 1966.

Horan, James David. Timothy O'Sullivan, America's Forgotten Photographer; the Life and Work of the Brilliant Photographer Whose Camera Recorded the American Scene from the Battlefields of the Civilo War to the Frontiers of the West. Doubleday, 1966.