Read Black and Scholes 1973, Black 1989 (How We Came Up With the Option Formula, JPM), and Sharpe, 1964, (Capital asset prices: A theory of market equilibrium under conditions of risk, JOF, 19(3), pp425-442) to see why these two papers are very important. In fact, I do not have the originals, but a combined version titled "Corporate Investment decisions" published by Treynor and Black in a book Modern Developments in Financial Management, edited by Stewart C. Myers, Praeger Publishers, New York, 1976 (sent to me by Jack Treynor from Treynor Capital Management, California). Yes, I am happy to send you a copy. You should also take a look at Treynor and Black's 1973 JB paper introducing the "appraisal ratio."