RT Journal Article SR Electronic T1 A New Approach to Ratings on Utility Bonds JF The Journal of Portfolio Management FD Institutional Investor Journals SP 63 OP 68 DO 10.3905/jpm.1979.408687 VO 5 IS 3 A1 Richard B. Edelman YR 1979 UL https://pm-research.com/content/5/3/63.abstract AB