Computations of superstring amplitudes in pure spinor formalism via   Cadabra
  The discovery of pure spinor formalism makes the computation of superstring scattering amplitudes possible. In this paper, we will illustrate how computer algebra system Cadabra is used in computing the supersymmetric amplitude in pure spinor formalism and provide the source code that computes the tree-level massless 5-gluon amplitude. 
Ke-Sheng Sun, Xiang-Mao Ding, Fei Sun, Hai-Bin Zhang
hep-th