%0 Journal Article %A Leonard F. Richardson %T N-step nilpotent Lie groups with flat Kirillov orbits %J Colloquium Mathematicum %D 1987 %P 285-287 %V 52 %N 2 %I mathdoc %U http://geodesic.mathdoc.fr/articles/10.4064/cm-52-2-285-287/ %R 10.4064/cm-52-2-285-287 %G en %F 10_4064_cm_52_2_285_287