  In this paper we demonstrate the direct evidence of solitons in graphene by
means of molecular dynamics simulations and mathematical analysis. It shows
various solitons emerge in the graphene flakes with two different chiralities
by cooling procedures. They are in-plane longitudinal and transverse solitons.
Their propagations and collisions are studied in details. A soliton solution is
derived by making several valid simplifications. We hope it shed light on
understanding the unusual thermal properties of graphene.
