Unger, F. W. (1901). With "Bobs" and Krüger: Experiences and observations of an American war correspondent in the field with both armies, illustrated from photographs taken by the author. Philadelphia: H.T. Coates and Company.

Unger, Frederic William. With "Bobs" and Krüger: Experiences and Observations of an American War Correspondent in the Field With Both Armies, Illustrated From Photographs Taken By the Author. Philadelphia: H.T. Coates and Company, 1901.

Unger, Frederic William. With "Bobs" and Krüger: Experiences and Observations of an American War Correspondent in the Field With Both Armies, Illustrated From Photographs Taken By the Author. Philadelphia: H.T. Coates and Company, 1901.