RT Journal Article SR Electronic T1 Kondratieff 1588 JF The Journal of Portfolio Management FD Institutional Investor Journals SP 70 OP 71 DO 10.3905/jpm.1980.408747 VO 6 IS 3 A1 Garrett Mattingly YR 1980 UL https://pm-research.com/content/6/3/70.abstract AB