diff --git a/src/systems/si-hep/include/units/isq/si/hep/area.h b/src/systems/si-hep/include/units/isq/si/hep/area.h
index fa5d8bdb..53aa3603 100644
--- a/src/systems/si-hep/include/units/isq/si/hep/area.h
+++ b/src/systems/si-hep/include/units/isq/si/hep/area.h
@@ -94,7 +94,7 @@ using namespace area_references;
 
 namespace units::aliases::isq::si::hep::inline area {
 
-template<Representation Rep = double> using barn = units::isq::si::hep::area<units::isq::si::hep::barn, Rep>;
+template<Representation Rep = double> using barn = units::isq::si::area<units::isq::si::hep::barn, Rep>;
 
 }  // namespace units::aliases::isq::si::hep::inline area
 
diff --git a/src/systems/si-hep/include/units/isq/si/hep/energy.h b/src/systems/si-hep/include/units/isq/si/hep/energy.h
index 87f8e9dd..25c42a8d 100644
--- a/src/systems/si-hep/include/units/isq/si/hep/energy.h
+++ b/src/systems/si-hep/include/units/isq/si/hep/energy.h
@@ -45,7 +45,7 @@ struct meV : prefixed_unit<meV, milli, electronvolt> {};
 using eV = electronvolt;
 struct keV : prefixed_unit<keV, kilo, electronvolt> {};
 struct MeV : prefixed_unit<MeV, mega, electronvolt> {};
-struct GeV : prefixed_unit<GeV, giga, electronvolt> {};
+using GeV = gigaelectronvolt;
 struct TeV : prefixed_unit<TeV, tera, electronvolt> {};
 struct PeV : prefixed_unit<PeV, peta, electronvolt> {};
 struct EeV : prefixed_unit<EeV, exa, electronvolt> {}; // N.B. very rarely used