diff --git a/pom.xml b/pom.xml
index edf73df..eee9935 100644
--- a/pom.xml
+++ b/pom.xml
@@ -5,7 +5,7 @@
     <groupId>eu.dnetlib.dhp</groupId>
     <artifactId>dhp-schemas</artifactId>
     <packaging>jar</packaging>
-    <version>2.9.25-SNAPSHOT</version>
+    <version>2.9.24-SNAPSHOT</version>
 
     <licenses>
         <license>
diff --git a/src/main/java/eu/dnetlib/dhp/schema/common/ModelSupport.java b/src/main/java/eu/dnetlib/dhp/schema/common/ModelSupport.java
index c93a45c..8639d55 100644
--- a/src/main/java/eu/dnetlib/dhp/schema/common/ModelSupport.java
+++ b/src/main/java/eu/dnetlib/dhp/schema/common/ModelSupport.java
@@ -158,16 +158,6 @@ public class ModelSupport {
 		}
 	}
 
-	private RelationInverse findInverse(String encoding) {
-		return ModelSupport.relationInverseMap
-				.entrySet()
-				.stream()
-				.filter(r -> encoding.equalsIgnoreCase(r.getKey()))
-				.findFirst()
-				.map(r -> r.getValue())
-				.orElseThrow(() -> new IllegalArgumentException("invalid relationship: " + encoding));
-	}
-
 	/**
 	 * Helper method: fina a relation filtering by a relation name
  	 * @param relationName