The logic of scientific discovery /

by Popper, Karl Raimund, Sir, 1902-,
Published 1983

The logic of scientific discovery /

by Popper, Karl Raimund, Sir, 1902-.
Published 1972

Tang guo zhi shi huo de : jie fang =

by Popper, Karl Raimund, Sir, 1902-1994.
Published 1998