# Heisenberg groups, Carnot groups and contact forms

The horizontal distribution in the Heisenberg group is the kernel of the standard contact form: $$\alpha = dt + 2 \sum_{j=1}^n (x_j \, dy_j - y_j \, dx_j).$$

Question. Can one describe horizontal distribution in any Carnot group in terms of kernels of some $$1$$-forms?

I believe the answer should be in the positive and I am looking for references for explicit constructions of such forms so that in the case of the Heisenberg group these constructions would give the contact form.