Ekelund,robert b. A history of economic theory and method [[Textbook] /] Robert b.Ekelund,Robert F.Hebert. - 4th ed. - new york : the mc graw - hill companies , 1997. - xvii,602p ; 24 cm. ISBN: 0071142827 Dewey Class. No.: 330.09 National Library of Medicine Call No.: 330.09 / EH