RT Journal Article SR Electronic T1 Comment JF The Journal of Portfolio Management FD Institutional Investor Journals SP 89 OP 90 DO 10.3905/jpm.1981.408784 VO 7 IS 2 A1 Harvey M. Salkin A1 Peter H. Ritchken YR 1981 UL https://pm-research.com/content/7/2/89.abstract AB