The Oxford Dictionary of Political Quotations

As one would expect, this is a comprehensive volume arranged by person and with an index of themes at the end. Needless to say it is full of gems: 'When the President does it, that means that it is not illegal' (Nixon but might have been Chirac..); 'wherever books will be burned, men also, in the end, are burned' (Heine); 'among the defects of the bill, which were numerous, one provision was conspicuous by its presence and another by its absence' (Lord John Russell, first Earl Russell).