PT - JOURNAL ARTICLE AU - Frederick L. Muller AU - Bruce D. Fielitz TI - Standard & Poor's Quality Rankings Revisited AID - 10.3905/jpm.1987.64 DP - 1987 Apr 30 TA - The Journal of Portfolio Management PG - 64--68 VI - 13 IP - 3 4099 - https://pm-research.com/content/13/3/64.short 4100 - https://pm-research.com/content/13/3/64.full