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

[Member of the International Brigades engaged in house-to-house fighting around the slaughterhouses near the University City, Madrid]

[Member of the International Brigades engaged in house-to-house fighting around 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]

[Republican bunkers around the Clinical Hospital, one of the principal bastions of the Nationalist rebels in the University City, Madrid]

[Republican bunkers around the Clinical Hospital, one of the principal bastions of the Nationalist rebels in the University City, Madrid]

[Building destroyed by Nationalist air raids, Madrid]

[A family portrait and other belongings on the street after an air raid, Madrid]

[Woman after an air raid, Madrid]

[Group of women and children living on the platforms of subway stations in the aftermath of Nationalist air raids, Madrid]

[Amored car used by officers of the International Brigades, Madrid]

[Soldiers reading behind Republican lines, Madrid]

[Refugee from Málaga sitting on bedding, Almeria, Spain]

[People sitting near the shelters so that they would not have to run every time the air raid alarm sounded, Bilbao, Spain]

[Republican soldiers during the battle for this strategically located hilltop town, Teruel, Aragón front, Spain]

[Republican soldiers on a staircase during the battle for this strategically located hilltop town, Teruel, Aragón front, Spain]

[Farewell ceremony for the International Brigades, Les Masies, Spain]

[Farewell ceremony for the International Brigades, Les Masies, Spain]

[Parade at the farewell ceremony for the International Brigades, near Falset, Spain]

[Major Milton Wolff, commander of the American Abraham Lincoln Brigade, near Falset, Spain]

[Telephone call to army command, Rio Segre, Aragón front, near Fraga, Spain]

[Marineros bringing in the wounded, Rio Segre, Aragón front, near Fraga, Spain]

[Marineros bringing in the wounded, Rio Segre, Aragón front, near Fraga, Spain]

[Crowd watching an air battle over the city, Barcelona]