RT Journal Article SR Electronic T1 S&P Quality Group Rankings JF The Journal of Portfolio Management FD Institutional Investor Journals SP 39 OP 42 DO 10.3905/jpm.1983.39 VO 9 IS 4 A1 Frederick L. Muller A1 Bruce D. Fielitz A1 Myron T. Greene YR 1983 UL https://pm-research.com/content/9/4/39.abstract AB