RT Journal Article SR Electronic T1 Toward enhancing beta estimates JF The Journal of Portfolio Management FD Institutional Investor Journals SP 43 OP 46 DO 10.3905/jpm.1980.408768 VO 6 IS 4 A1 Joseph A Lavely A1 Gordon Wakefield A1 Bob Barrett YR 1980 UL https://pm-research.com/content/6/4/43.abstract AB