← Search Econometrica Vol. 8 No. 2 1940 The Approximate Determination of Indifference Surfaces by Means of Engel Curves A. Wald DOI10.2307/1907033 Volume8 Issue2 Pages144 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 ✓