The exactly integrable systems connected with semisimple algebras of the   second rank $A_2,B_2,C_2,G_2$
  All exactly integrable systems connected with the semisimple algebras of the second rank with an arbitrary choice of the grading in them are presented in explicit form. General solution of such systems are expressed in terms of the matrix elements of two fundamental representations of corresponding semisimple groups. 
A. N. Leznov