  An action for the ten-dimensional Green-Schwarz superstring with N=2
worldsheet superconformal invariance has recently been used to calculate
superstring scattering amplitudes and prove their finiteness. In this paper, it
is shown that the N=2 stress-energy tensor for this Green-Schwarz action can be
constructed out of the stress-energy tensor and ghosts of the Neveu-
Schwarz-Ramond action by the standard twisting procedure. In other words, a
field redefinition is found from the GS matter fields into the NSR matter and
ghost fields which transforms the matter part of the two fermionic GS super-
conformal generators into the $b$ ghost and shifted BRST current of the NSR
string. In light-cone gauge, this field redefinition reduces to the usual one
relating the light-cone GS and NSR fields.
  Although this proves the equivalence of physical vertex operators in the two
superstring formalisms, multiloop amplitudes are easier to calculate using the
Green-Schwarz formalism since manifest spacetime supersymmetry eliminates the
need for spin cuts, GSO projections, and cutoffs in moduli space.
