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 ### Built With
 The current release of the proton response files is based on:
-* Geant4 v10.4
+* Geant4 v10.4 [Agostinelli et al. NIMPA, 506, 250, 2003; Allison et al. ITNS, 53, 270, 2006; Allison et al. NIMPA, 835, 186, 2016]
 * BoGEMMS v2.1 [Fioretti et al., Proc. SPIE, 118221F, 2021]
 * Ray-tracing Monte Carlo code [Mineo et al., Exp. Astr., 44, 287, 2017]