%0 Journal Article %A Andreas C Christofi %T How to Maximize Stationarity of Beta %B A Comment %D 1983 %R 10.3905/jpm.1983.67 %J The Journal of Portfolio Management %P 67-68 %V 9 %N 4 %U https://jpm.pm-research.com/content/iijpormgmt/9/4/67.full.pdf