diff --git a/src/models/ConstrainedMetaModel.ts b/src/models/ConstrainedMetaModel.ts
index 928b24ca65..eaca070f9c 100644
--- a/src/models/ConstrainedMetaModel.ts
+++ b/src/models/ConstrainedMetaModel.ts
@@ -55,6 +55,9 @@ export class ConstrainedTupleModel extends ConstrainedMetaModel {
     ).map((tupleModel) => {
       return tupleModel.value = tupleModel.value as ConstrainedReferenceModel;
     });
+    //Ensure no duplicate references
+    dependencyModels = [...new Set(dependencyModels)];
+
     //Ensure no self references
     dependencyModels = dependencyModels.filter((referenceModel) => {
       return referenceModel.name !== this.name;
@@ -104,6 +107,9 @@ export class ConstrainedUnionModel extends ConstrainedMetaModel {
     ).map((unionModel) => {
       return unionModel as ConstrainedReferenceModel;
     });
+    //Ensure no duplicate references
+    dependencyModels = [...new Set(dependencyModels)];
+
     //Ensure no self references
     dependencyModels = dependencyModels.filter((referenceModel) => {
       return referenceModel.name !== this.name;
@@ -125,21 +131,6 @@ export class ConstrainedEnumModel extends ConstrainedMetaModel {
     public values: ConstrainedEnumValueModel[]) {
     super(name, originalInput, type);
   }
-
-  getNearestDependencies(): ConstrainedReferenceModel[] {
-    let dependencyModels = Object.values(this.values).filter(
-      (enumModel) => {
-        return enumModel.value instanceof ConstrainedReferenceModel;
-      }
-    ).map((enumModel) => {
-      return enumModel.value as ConstrainedReferenceModel;
-    });
-    //Ensure no self references
-    dependencyModels = dependencyModels.filter((referenceModel) => {
-      return referenceModel.name !== this.name;
-    });
-    return dependencyModels;
-  }
 }
 export class ConstrainedDictionaryModel extends ConstrainedMetaModel {
   constructor(
@@ -161,6 +152,9 @@ export class ConstrainedDictionaryModel extends ConstrainedMetaModel {
     ).map((model) => {
       return model as ConstrainedReferenceModel;
     });
+    //Ensure no duplicate references
+    dependencyModels = [...new Set(dependencyModels)];
+
     //Ensure no self references
     dependencyModels = dependencyModels.filter((referenceModel) => {
       return referenceModel.name !== this.name;
@@ -186,6 +180,9 @@ export class ConstrainedObjectModel extends ConstrainedMetaModel {
     ).map((modelProperty) => {
       return modelProperty.property as ConstrainedReferenceModel;
     });
+    //Ensure no duplicate references
+    dependencyModels = [...new Set(dependencyModels)];
+
     //Ensure no self references
     dependencyModels = dependencyModels.filter((referenceModel) => {
       return referenceModel.name !== this.name;
diff --git a/test/blackbox/blackbox.spec.ts b/test/blackbox/blackbox.spec.ts
index ff8ed0ca4c..0dd09c4d63 100644
--- a/test/blackbox/blackbox.spec.ts
+++ b/test/blackbox/blackbox.spec.ts
@@ -45,6 +45,9 @@ const filesToTest = [
   }).filter(({ file }) => {
     // Related to https://github.com/asyncapi/modelina/issues/389
     return !file.includes('jenkins-config.json');
+  }).filter(({file}) => {
+    // Related to https://github.com/asyncapi/modelina/issues/840
+    // Related to https://github.com/asyncapi/modelina/issues/841
   }).filter(({ file }) => {
     // Related to https://github.com/asyncapi/modelina/issues/825
     return !file.includes('circleci-config.json');
diff --git a/test/models/ConstrainedMetaModel.spec.ts b/test/models/ConstrainedMetaModel.spec.ts
index 438a7bcb23..08d1e18b1e 100644
--- a/test/models/ConstrainedMetaModel.spec.ts
+++ b/test/models/ConstrainedMetaModel.spec.ts
@@ -99,6 +99,23 @@ describe('ConstrainedMetaModel', () => {
       expect(dependencies).toHaveLength(1);
       expect(dependencies[0]).toEqual(model.tuple[0].value);
     });
+
+    test('should not return duplicate dependencies', () => {
+      const stringModel = new StringModel('', undefined);
+      const referenceModel = new ReferenceModel('', undefined, stringModel);
+      const referenceTupleModel = new TupleValueModel(0, referenceModel);
+      const reference2TupleModel = new TupleValueModel(1, referenceModel);
+      const rawModel = new TupleModel('test', undefined, [referenceTupleModel, reference2TupleModel]);
+      
+      const model = constrainMetaModel(mockedTypeMapping, mockedConstraints, {
+        metaModel: rawModel,
+        constrainedName: '',
+        options: undefined
+      }) as ConstrainedTupleModel;
+      const dependencies = model.getNearestDependencies();
+      expect(dependencies).toHaveLength(1);
+      expect(dependencies[0]).toEqual(model.tuple[0].value);
+    });
   });
   describe('ObjectModel', () => {
     test('should return all reference dependencies', () => {
@@ -121,6 +138,26 @@ describe('ConstrainedMetaModel', () => {
       expect(dependencies[0]).toEqual(model.properties['reference'].property);
     });
 
+    test('should not return duplicate dependencies', () => {
+      const stringModel = new StringModel('string', undefined);
+      const referenceModel = new ReferenceModel('reference', undefined, stringModel);
+      const referenceObjectPropertyModel = new ObjectPropertyModel('reference', false, referenceModel);
+      const reference2ObjectPropertyModel = new ObjectPropertyModel('reference2', false, referenceModel);
+      const rawModel = new ObjectModel('test', undefined, {
+        reference: referenceObjectPropertyModel,
+        reference2: reference2ObjectPropertyModel
+      });
+      
+      const model = constrainMetaModel(mockedTypeMapping, mockedConstraints, {
+        metaModel: rawModel,
+        constrainedName: '',
+        options: undefined
+      }) as ConstrainedObjectModel;
+      const dependencies = model.getNearestDependencies();
+      expect(dependencies).toHaveLength(1);
+      expect(dependencies[0]).toEqual(model.properties['reference'].property);
+    });
+
     describe('containsPropertyType', () => {
       test('should find present property type and those who are not', () => {
         const stringModel = new ConstrainedStringModel('', undefined, '');
@@ -154,6 +191,20 @@ describe('ConstrainedMetaModel', () => {
       const referenceModel = new ReferenceModel('', undefined, stringModel);
       const rawModel = new DictionaryModel('test', undefined, referenceModel, stringModel);
       
+      const model = constrainMetaModel(mockedTypeMapping, mockedConstraints, {
+        metaModel: rawModel,
+        constrainedName: '',
+        options: undefined
+      }) as ConstrainedDictionaryModel;
+      const dependencies = model.getNearestDependencies();
+      expect(dependencies).toHaveLength(1);
+      expect(dependencies[0]).toEqual(model.key);
+    });
+    test('should not return duplicate dependencies', () => {
+      const stringModel = new StringModel('', undefined);
+      const referenceModel = new ReferenceModel('', undefined, stringModel);
+      const rawModel = new DictionaryModel('test', undefined, referenceModel, referenceModel);
+      
       const model = constrainMetaModel(mockedTypeMapping, mockedConstraints, {
         metaModel: rawModel,
         constrainedName: '',
@@ -207,5 +258,20 @@ describe('ConstrainedMetaModel', () => {
       expect(dependencies).toHaveLength(1);
       expect(dependencies[0]).toEqual(model.union[0]);
     });
+
+    test('should not return duplicate dependencies', () => {
+      const stringModel = new StringModel('', undefined);
+      const referenceModel = new ReferenceModel('', undefined, stringModel);
+      const rawModel = new UnionModel('test', undefined, [referenceModel, referenceModel]);
+      
+      const model = constrainMetaModel(mockedTypeMapping, mockedConstraints, {
+        metaModel: rawModel,
+        constrainedName: '',
+        options: undefined
+      }) as ConstrainedUnionModel;
+      const dependencies = model.getNearestDependencies();
+      expect(dependencies).toHaveLength(1);
+      expect(dependencies[0]).toEqual(model.union[0]);
+    });
   });
 });