MAP20130018782 Letter in response to Fraas & Lutter Article: Uncertain benefits estimates for reductions in fine particle concentrations / Neal Fann... [et al.] En: Risk analysis : an international journal. - McLean, Virginia : Society for Risk Analysis, 1987-2015 = ISSN 0272-4332. - 01/05/2013 Volumen 33 Número 5 - mayo 2013 I. Fann, Neal .