EN
Andrzej Dudek: Symbolic data analysis methods in economic research, published by the Wroclaw University of Economics, Wroclaw 2013, p. 230
FR
Andrzej Dudek: Methodes d’analyse des donnees symboliques relatives aux enquetes economiques, Maison d’edition de l’Universite Economique a Wrocław, Wrocław 2013, page 230