Zeuthen, F. b. 1888. Economic theory and method. [electronic resource] . — Cambridge, : Harvard University Press,, 1955.. — xii, 364 p. : diagrs. 23 cm.
"Translation of ... Økonomisk teori of metode (... Copenhage 1942) thoroughly revised and considerably enlarged."
"Literature in English by authors from northern countries": p. 347-353. Bibliographical footnotes.