Differential Conformal Superalgebras and their Forms
  We introduce the formalism of differential conformal superalgebras, which we show leads to the "correct" automorphism group functor and accompanying descent theory in the conformal setting. As an application, we classify forms of N=2 and N=4 conformal superalgebras by means of Galois cohomology. 
Victor Kac, Michael Lau, Arturo Pianzola