PT - JOURNAL ARTICLE AU - Richard B. Edelman TI - Telecommunications betas AID - 10.3905/jpm.1983.408936 DP - 1983 Oct 31 TA - The Journal of Portfolio Management PG - 46--52 VI - 10 IP - 1 4099 - https://pm-research.com/content/10/1/46.short 4100 - https://pm-research.com/content/10/1/46.full