Simple multiplicative proof nets with units
  This paper presents a simple notion of proof net for multiplicative linear logic with units. Cut elimination is direct and strongly normalising, in contrast to previous approaches which resorted to moving jumps (attachments) of par units during normalisation. Composition in the resulting category of proof nets is simply path composition: all of the dynamics happens in GoI(Setp), the geometry-of-interaction construction applied to the category of sets and partial functions. 
Dominic Hughes