Wright, G. H. von, 1916-2003 An essay in modal logic / Georg H. von Wright

An essay in modal logic / Georg H. von Wright . - xxa Amsterdam xxa-fimyyc North-Holland yyc-fim, 1951 . - 90 p. : il. 22 cm . - (Studies in logic and the foundations of mathematics / L. E. J. Brouwer, E. W. Beth, A. Heyting, editors)