  Since proof-nets for MLL- were introduced by Girard (1987), several studies
have appeared dealing with its soundness proof. Bellin & Van de Wiele (1995)
produced an elegant proof based on properties of subnets (empires and kingdoms)
and Robinson (2003) proposed a straightforward generalization of this
presentation for proof-nets from sequent calculus for classical logic. In 2014
it was presented an extension of these studies to obtain a proof of the
sequentialization theorem for the fragment of N-Graphs with conjunction,
disjunction and negation connectives, via the notion of sub-N-Graphs. N-Graphs
is a symmetric natural deduction calculus with multiple conclusions that adopts
Danos-Regnier's criterion and has defocussing switchable links. In this paper,
we present a sequentization for full propositional classical N-Graphs, showing
how to find a split node in the middle of the proof even with a global rule for
discharging hypothesis.
