2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/221252We define a normalized impact factor suitable to assess in a simple way both the strength of scientific communities and the research influence of individuals. We define those ones with $NIF \geq 1$ as being scientific leaders since they would influence their peers at least as much as they are influenced by them. The NIF is distinguished because (a) this has a clear and universal meaning being applicable with equal efficiency to individuals belonging to scientific communities with quite different publication and citation traditions and (b) this is robust against self-citation expedient. This is eventually applied to a community derived from the list of outstanding referees recognized by the American Physical Society in 2008.2 pages and 2 figuresPhysics and SocietyData Analysis, Statistics and Probabilitytext