PT - JOURNAL ARTICLE AU - James C. Ryan AU - Mark Kritzman TI - Catch 500 AID - 10.3905/jpm.1980.408725 DP - 1980 Jan 31 TA - The Journal of Portfolio Management PG - 30--32 VI - 6 IP - 2 4099 - https://pm-research.com/content/6/2/30.short 4100 - https://pm-research.com/content/6/2/30.full