RT Journal Article SR Electronic T1 The ill-behaved e's JF The Journal of Portfolio Management FD Institutional Investor Journals SP 1 OP 3 DO 10.3905/jpm.1987.409118 VO 13 IS 4 A1 Peter L. Bernstein YR 1987 UL https://pm-research.com/content/13/4/1.abstract AB