PT - JOURNAL ARTICLE AU - John M. Cheney TI - Rating classification and bond yield volatility AID - 10.3905/jpm.9.3.51 DP - 1983 Apr 30 TA - The Journal of Portfolio Management PG - 51--57 VI - 9 IP - 3 4099 - https://pm-research.com/content/9/3/51.short 4100 - https://pm-research.com/content/9/3/51.full