diff --git a/modules/swagger-parser-v3/src/main/java/io/swagger/v3/parser/processors/ExternalRefProcessor.java b/modules/swagger-parser-v3/src/main/java/io/swagger/v3/parser/processors/ExternalRefProcessor.java
index 8f9edfd323..e43735368d 100644
--- a/modules/swagger-parser-v3/src/main/java/io/swagger/v3/parser/processors/ExternalRefProcessor.java
+++ b/modules/swagger-parser-v3/src/main/java/io/swagger/v3/parser/processors/ExternalRefProcessor.java
@@ -15,6 +15,7 @@
 import io.swagger.v3.oas.models.security.SecurityScheme;
 import io.swagger.v3.parser.ResolverCache;
 import io.swagger.v3.parser.models.RefFormat;
+import org.apache.commons.lang3.StringUtils;
 import org.slf4j.LoggerFactory;
 
 import java.net.URI;
@@ -97,7 +98,8 @@ public String processRefToExternalSchema(String $ref, RefFormat refFormat) {
                         processRefProperty(prop.getValue(), file);
                     } else if (prop.getValue() instanceof ArraySchema) {
                         ArraySchema arrayProp = (ArraySchema) prop.getValue();
-                        if (arrayProp.getItems().get$ref() != null) {
+                        if (arrayProp.getItems() != null && arrayProp.getItems().get$ref() != null &&
+                                StringUtils.isNotBlank(arrayProp.get$ref())) {
                             processRefProperty(arrayProp.getItems(), file);
                         }
                     } else if (prop.getValue().getAdditionalProperties() != null) {
@@ -105,13 +107,39 @@ public String processRefToExternalSchema(String $ref, RefFormat refFormat) {
                         if (mapProp.getAdditionalProperties().get$ref() != null) {
                             processRefProperty(mapProp.getAdditionalProperties(), file);
                         } else if (mapProp.getAdditionalProperties() instanceof ArraySchema &&
-                                ((ArraySchema) mapProp.getAdditionalProperties()).getItems().get$ref() != null) {
+                                    ((ArraySchema) mapProp.getAdditionalProperties()).getItems()!= null &&
+                                        ((ArraySchema) mapProp.getAdditionalProperties()).getItems().get$ref() != null
+                                        && StringUtils.isNotBlank(((ArraySchema) mapProp.getAdditionalProperties()).getItems().get$ref())) {
                             processRefProperty(((ArraySchema) mapProp.getAdditionalProperties()).getItems(), file);
                         }
                     }
                 }
             }
-            if (schema instanceof ArraySchema && ((ArraySchema) schema).getItems().get$ref() != null) {
+            if(schema.getAdditionalProperties() != null){
+                Schema additionalProperty = schema.getAdditionalProperties();
+                if (additionalProperty.get$ref() != null) {
+                    processRefProperty(additionalProperty, file);
+                } else if (additionalProperty instanceof ArraySchema) {
+                    ArraySchema arrayProp = (ArraySchema) additionalProperty;
+                    if (arrayProp.getItems() != null && arrayProp.getItems().get$ref() != null &&
+                            StringUtils.isNotBlank(arrayProp.get$ref())) {
+                        processRefProperty(arrayProp.getItems(), file);
+                    }
+                } else if (additionalProperty.getAdditionalProperties() != null) {
+                    Schema mapProp =  additionalProperty;
+                    if (mapProp.getAdditionalProperties().get$ref() != null) {
+                        processRefProperty(mapProp.getAdditionalProperties(), file);
+                    } else if (mapProp.getAdditionalProperties() instanceof ArraySchema &&
+                                ((ArraySchema) mapProp.getAdditionalProperties()).getItems() != null &&
+                                    ((ArraySchema) mapProp.getAdditionalProperties()).getItems().get$ref() != null
+                                    && StringUtils.isNotBlank(((ArraySchema) mapProp.getAdditionalProperties()).getItems().get$ref()))  {
+                        processRefProperty(((ArraySchema) mapProp.getAdditionalProperties()).getItems(), file);
+                    }
+                }
+
+            }
+            if (schema instanceof ArraySchema && ((ArraySchema) schema).getItems() != null && ((ArraySchema) schema).getItems().get$ref() != null
+                    && StringUtils.isNotBlank(((ArraySchema) schema).getItems().get$ref())) {
                 processRefProperty(((ArraySchema) schema).getItems(), file);
             }
         }
diff --git a/modules/swagger-parser-v3/src/test/java/io/swagger/v3/parser/test/OpenAPIV3ParserTest.java b/modules/swagger-parser-v3/src/test/java/io/swagger/v3/parser/test/OpenAPIV3ParserTest.java
index 9473e48a49..c073793bd5 100644
--- a/modules/swagger-parser-v3/src/test/java/io/swagger/v3/parser/test/OpenAPIV3ParserTest.java
+++ b/modules/swagger-parser-v3/src/test/java/io/swagger/v3/parser/test/OpenAPIV3ParserTest.java
@@ -303,6 +303,17 @@ public void testInlineModelResolverByUrl(@Injectable final List<AuthorizationVal
         assertNotNull(userAddress.getProperties().get("street"));
     }
 
+    @Test
+    public void testRefAdditionalProperties() throws Exception {
+        OpenAPI openAPI = new OpenAPIV3Parser().read("src/test/resources/additionalProperties.yaml");
+
+        Assert.assertNotNull(openAPI);
+        Assert.assertTrue(openAPI.getComponents().getSchemas().size() == 3);
+        Assert.assertNotNull(openAPI.getComponents().getSchemas().get("link-object"));
+        Assert.assertNotNull(openAPI.getComponents().getSchemas().get("rel-data"));
+        Assert.assertNotNull(openAPI.getComponents().getSchemas().get("result"));
+    }
+
 
     private static int getDynamicPort() {
         return new Random().ints(10000, 20000).findFirst().getAsInt();
diff --git a/modules/swagger-parser-v3/src/test/resources/additionalProperties.yaml b/modules/swagger-parser-v3/src/test/resources/additionalProperties.yaml
new file mode 100644
index 0000000000..a8f93da168
--- /dev/null
+++ b/modules/swagger-parser-v3/src/test/resources/additionalProperties.yaml
@@ -0,0 +1,18 @@
+---
+openapi: 3.0.0
+servers:
+- url: http://swagger.io/show-bug
+info:
+  title: Test API
+  version: 1.0.0
+paths:
+  "/tests":
+    get:
+      operationId: listTests
+      responses:
+        '200':
+          description: Returns results.
+          content:
+            application/json:
+              schema:
+                "$ref": "./globals.yaml#/components/schemas/result"
\ No newline at end of file
diff --git a/modules/swagger-parser-v3/src/test/resources/globals.yaml b/modules/swagger-parser-v3/src/test/resources/globals.yaml
new file mode 100644
index 0000000000..14cfbe2895
--- /dev/null
+++ b/modules/swagger-parser-v3/src/test/resources/globals.yaml
@@ -0,0 +1,22 @@
+components:
+  schemas:
+    link-object:
+      type: object
+      additionalProperties:
+        "$ref": "#/components/schemas/rel-data"
+    rel-data:
+      type: object
+      required:
+      - href
+      properties:
+        href:
+          type: string
+        note:
+          type: string
+    result:
+      type: object
+      properties:
+        name:
+          type: string
+        _links:
+          "$ref": "#/components/schemas/link-object"