diff --git a/dxm/src/main/java/io/pcp/parfait/dxm/semantics/UnitMapping.java b/dxm/src/main/java/io/pcp/parfait/dxm/semantics/UnitMapping.java
index <HASH>..<HASH> 100644
--- a/dxm/src/main/java/io/pcp/parfait/dxm/semantics/UnitMapping.java
+++ b/dxm/src/main/java/io/pcp/parfait/dxm/semantics/UnitMapping.java
@@ -76,7 +76,7 @@ public final class UnitMapping {
             return false;
         }
         Unit<?> divided = left.divide(right);
-        if (!divided.getDimension().equals(NONE)) {
+        if (!divided.getDimension().equals(Dimension.NONE)) {
             return false;
         }
         return divided.asType(Dimensionless.class).getConverterTo(ONE).equals(IDENTITY);
Resolve a type issue found by Coverity scanning

We were using Unit.NONE instead of Dimension.NONE
in one call site by accident.  In practice not an
issue, by good fortune, but may as well fix it up.