Popper, Karl R. (Karl Raimund), Conjectures and refutations : the growth if scientific knowledge / by Karl R. Popper. - 1a ed. - London ; Routledge and Kegan paul, 1963 - 412 p. ; 26 cm. Subjects--Topical Terms: Ciencia--Filosofía LC Class. No.: Q171 / P67 1963