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Harald Gordon Skilling (1981) Charter 77 and human rights in Czechoslovakia, London, Allen & Unwin.
What Charter 77 is and what it is not
Jan Patočka
pp. 217-219
Not implemented yet !
(1977) "Čím je a čím není Charta 77", in: Vladislav Jan, Jan Patočka, Praha, Kvart, pp.11-13.