BUTLER, D., & Butler, D. . a. S. (1980). British political facts, 1900- 1967 (5th ed.). Palgrave Macmillan.
Chicago Style (17th ed.) ZitazioaBUTLER, David, eta David and Sloman Butler. British Political Facts, 1900- 1967. 5th ed. London: Palgrave Macmillan, 1980.
MLA (9th ed.) ZitazioaBUTLER, David, eta David and Sloman Butler. British Political Facts, 1900- 1967. 5th ed. Palgrave Macmillan, 1980.
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