Ware, C. F., Panikkar, K. M., & Romein, J. M. (1966). The twentieth century. Unwin Brothers.
Lua i Stíl Chicago (17ú heag.)Ware, Caroline F., K. M. Panikkar, agus J. M. Romein. The Twentieth Century. London: Unwin Brothers, 1966.
Lua MLA (9ú heag.)Ware, Caroline F., et al. The Twentieth Century. Unwin Brothers, 1966.
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