Before revision:  Here we present a direct route, independent of the dimension of the stoichiometric space which precludes at the same time the existence of degenerate steady states  .
After revision:  Here we present a direct route, independent of the dimension of the stoichiometric space which precludes at the same time the existence of degenerate steady states . Further, we relate injectivity of a chemical reaction network to that of the chemical reaction network obtained by adding outflow reactions for all species .