[Republican soldiers camping in a physics laboratory, University City, Madrid]

[Republican soldiers firing machine guns, University City, Madrid]

[Member of the International Brigades defending a building in the University City, Madrid]

[Republican officer and Gerda Taro (right), University City, Madrid]

[Republican soldier aiming rifle through a wall, University City, Madrid]

[Republican soldier aiming rifle through wall, University City, Madrid]

[Republican soldier helping wounded comrade to safety, University City, Madrid]

[Republican soldier aiming rifle through peephole, University City, Madrid]

[Member of the International Brigades behind a barricade, in or around University City, Madrid]

[Republican soldiers aiming rifles through window, University City, Madrid]

[Republican soldier stepping through a hole in a wall, University City, Madrid]

[Republican soldiers behind barricade made of sandbags and luggage, University City, Madrid]

[Republican soldiers aiming machine guns through peepholes, University City, Madrid]

[Members of the International Brigades with guns behind a barricade, in or around University City, Madrid]

[Republican soldiers aiming machine guns through peepholes, University City, Madrid]

[Men of the International Brigades in a laboratory of the Medical School building of the University City, Madrid]

[Two Republican soldiers sitting and talking in the street near University City, Madrid

[Two Republican soldiers sitting and talking in the street near University City, Madrid

[Students writing at desks, Israel]

[Students writing at desks, Israel]

[Members of the International Brigades with gun, looking out a window, in or around University City, Madrid]

[Two Republican soldiers aiming rifles through barricaded window, University City, Madrid]

[Men of the International Brigades catapulting grenades in the vicinity of the slaughterhouses near the University City, Madrid]

[Member of the International Brigades helping a wounded comrade in the vicinity of the slaughterhouses near the University City, Madrid]