Huyghe, Rene, Larousse encyclopedia of modern art: from l800 to the present day.Paul Hamlyn, 1981.
Includes fine art and other branches - craft, architecture - by country and period.

Wolf, Norbert. "Expressionism". Taschen Basic Art Series. In print.
Other titles relevant to Bruno Beran's life in the Taschen series deal with Brucke, Impressionism, Kandinsky, Kirchner, Klimt, Marc, Matisse, Monet, The Blaue Reiter.

Many of the individuals mentioned, including artists and sitters for portraits, and the political events that affected his life have Wikipedia entries. For example: