References
- C. R. Acad. Sci. Paris S´er.I v.318 Geometry of generalized Heisenberg groups and their DamakRicci harmonic extensions J. Berndt, F. Tricerri ;L. Vanhecke
- Ann. scient. Ecole Normale Sup v.27 Geometry of 2step Nilpotent Lie groups with a left invariant metric P. Eberlein
- Geom. Dedicata v.11 Riemannian Nilmanifolds attached to Clifford modules A. Kaplan
- Bull. London Math. Soc v.15 On the geometry of groups of Heisenberg Type A. Kaplan
- Indiana Univ. Math. Journal v.45 Smoothly Closed Geodesics in 2-step Nilmanifolds K. B. Lee;K. Park