Canonical description of D=10 superstring formulated in supertwistor   space
  Canonical description of the D=10 superstring action involving supertwistor variables generalizing Penrose-Ferber supertwistors is developed. Primary and secondary constraints are identified and arranged into the first- and second-class sets. Dirac brackets are introduced and the deformation of the Poisson bracket algebra of the first-class constraints is studied. The role of the deformation parameter is played by alpha'. 
D.V. Uvarov