Fundamental solutions for translation and rotation invariant differential operators on the Heisenberg group Priscilla Gorelli (2000) Colloquium Mathematicae
Fundamental solutions of differential operators on homogeneous manifolds of negative curvature and related Riesz transforms Ewa Damek (1997) Colloquium Mathematicae
Fundamental vector fields on associated fiber bundles Ivan Kolář (1977) Časopis pro pěstování matematiky