← Search Econometrica Vol. 40 No. 2 1972 Convex Structures and Economics Theory Martin Shubik; Hukukane Nikaidô DOI10.2307/1909425 Volume40 Issue2 Pages412 Sources semanticscholar openalex crossref Cite APA 7 MLA 9 Chicago (author–date) Harvard Elsevier Harvard (JFE, JBF…) The Accounting Review Academy of Management American Marketing Association INFORMS (Management Science) Copy citation Copied ✓