PT - JOURNAL ARTICLE AU - Michael G. Ferri TI - Reply AID - 10.3905/jpm.1979.71 DP - 1979 Jul 31 TA - The Journal of Portfolio Management PG - 71--72 VI - 5 IP - 4 4099 - https://pm-research.com/content/5/4/71.short 4100 - https://pm-research.com/content/5/4/71.full