RT Journal Article SR Electronic T1 Computing durations for bond portfolios JF The Journal of Portfolio Management FD Institutional Investor Journals SP 51 OP 55 DO 10.3905/jpm.1990.409304 VO 17 IS 1 A1 Gerald O. Bierwag A1 Charles J. Corrado A1 George G. Kaufman YR 1990 UL https://pm-research.com/content/17/1/51.abstract AB