On the Geometry of Null Polygons in Full N=4 Superspace
  We discuss various formulations of null polygons in full, non-chiral N=4 superspace in terms of spacetime, spinor and twistor variables. We also note that null polygons are necessarily fat along fermionic directions, a curious fact which is compensated by suitable equivalence relations in physical theories on this superspace. 
Niklas Beisert, Cristian Vergu
hep-th