I only regret the fact that this is a short paper , and there is therefore not enough space for a more formal description and discussion of the methodology	['non', 'non', 'non', 'non', 'non', 'non', 'con', 'con', 'con', 'con', 'con', 'non', 'non', 'con', 'con', 'con', 'con', 'con', 'con', 'con', 'con', 'con', 'con', 'con', 'con', 'con', 'con', 'con', 'con']	paper quality