On conformal invariant integrals involving spin one-half and spin-one   particles
  We consider the evaluation of D-dimensional conformal invariant integrals which involve spin one-half and spin-one particles. The star-triangle relation for the massless Yukawa theory is derived, and the longitudinal part of the three-point Green function of massless QED is determined to the lowest order in position space. The operator algebraic method of calculating massless Feynman integrals is used for the evaluation. 
Indrajit Mitra