M. W. Wong and Shengwen Yang: Heat semigroups and inverses of twisted
Laplacians on nonisotropic Heisenberg
groups with multi-dimensional center (PAFA)
Volume 7, Number 3, 1065-1084
Heat semigroups and inverses of twisted
Laplacians on nonisotropic Heisenberg
groups with multi-dimensional center M. W. Wong and Shengwen Yang