Affine Toda Solitons and Automorphisms of Dynkin Diagrams
  Using Hirota's method, solitons are constructed for affine Toda field theories based on the simply-laced affine algebras. By considering automorphisms of the simply-laced Dynkin diagrams, solutions to the remaining algebras, twisted as well as untwisted, are deduced. 
Niall MacKay and William McGhee