TY - JOUR AU - Ewa Damek TI - The geometry of a semi-direct extension of a Heisenberg type nilpotent group JO - Colloquium Mathematicum PY - 1987 SP - 255 EP - 268 VL - 53 IS - 2 PB - mathdoc UR - http://geodesic.mathdoc.fr/articles/10.4064/cm-53-2-255-268/ DO - 10.4064/cm-53-2-255-268 LA - en ID - 10_4064_cm_53_2_255_268 ER -