An integral representation for Folland's fundamental solution of the   sub-Laplacian on Heisenberg groups $\Bbb{H}^{n}$
  We prove that the Folland's fundamental solution for the sub-Laplacian on Heisenberg groups can also be derived form the resolvent kernel of this sub-Laplacian. This provides us with a new integral representation for this fundamental solution. 
Allal Ghanmi and Zouha\"ir Mouayn
math.SP