diff --git a/src/metkit/mars2grib/backend/concepts/reference-period/referencePeriodEncoding.h b/src/metkit/mars2grib/backend/concepts/reference-period/referencePeriodEncoding.h
index 8993e592..79cfdf0d 100644
--- a/src/metkit/mars2grib/backend/concepts/reference-period/referencePeriodEncoding.h
+++ b/src/metkit/mars2grib/backend/concepts/reference-period/referencePeriodEncoding.h
@@ -111,6 +111,8 @@ void ReferencePeriodOp(const MarsDict_t& mars, const ParDict_t& par, const OptDi
     static_cast<void>(opt);
     static_cast<void>(out);
 
+    using metkit::mars2grib::utils::exceptions::Mars2GribConceptException;
+
     if constexpr (referencePeriodApplicable<Stage, Section, Variant>()) {
 
         try {