← Search Journal of Finance Vol. 39 No. 2 1984 On Valuing American Call Options with the Black-Scholes European Formula Robert Geske; Richard Roll DOI10.2307/2327870 Volume39 Issue2 Pages443 Sources crossref semanticscholar openalex 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 ✓