%0 Journal Article
%A Zdzisław Porosiński
%A Marek Skarupski
%A Krzysztof Szajowski
%T Duration problem: basic concept and some extensions
%J Mathematica Applicanda
%D 2016
%P  87-112
%V 44
%N 1
%I mathdoc
%U http://geodesic.mathdoc.fr/articles/10.14708/ma.v44i1.829/
%R 10.14708/ma.v44i1.829
%G pl
%F 10_14708_ma_v44i1_829