RT Book T1 Conjectures and refutations: the growth of scientific knowledge A1 Popper, Karl R. 1902-1994 LA English PP London PB Routledge and Kegan Paul YR 1963 UL https://krimdok.uni-tuebingen.de/Record/1103907549 CN 001.012 K1 Erkenntnistheorie K1 Wissenschaftsphilosophie