diff --git a/src/com/amazonaws/service/apigateway/importer/impl/SchemaTransformer.java b/src/com/amazonaws/service/apigateway/importer/impl/SchemaTransformer.java
index f6a8962..b7815e8 100644
--- a/src/com/amazonaws/service/apigateway/importer/impl/SchemaTransformer.java
+++ b/src/com/amazonaws/service/apigateway/importer/impl/SchemaTransformer.java
@@ -17,6 +17,7 @@
 import com.fasterxml.jackson.core.JsonProcessingException;
 import com.fasterxml.jackson.databind.JsonNode;
 import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.SerializationFeature;
 import com.fasterxml.jackson.databind.node.JsonNodeFactory;
 import com.fasterxml.jackson.databind.node.ObjectNode;
 import com.fasterxml.jackson.databind.node.TextNode;
@@ -39,15 +40,15 @@ public class SchemaTransformer {
 
     /**
      * Get a schema schema in "flattened" form whereby all dependent references are resolved
-     * and included as inline schema definitions
+     * and included as external schema definitions
      *
      * @return the json-schema string in flattened form
      */
-    public String flatten(String model, String models) {
-        return getFlattened(deserialize(model), deserialize(models));
+    public String flatten(String apiId, String model, String models) {
+        return getFlattened(apiId, deserialize(model), deserialize(models));
     }
 
-    private void buildSchemaReferenceMap(JsonNode model, JsonNode models, Map<String, String> modelMap) {
+    private void buildSchemaReferenceMap(String apiId, JsonNode model, JsonNode models, Map<String, String> modelMap) {
         Map<JsonNode, JsonNode> refs = new HashMap<>();
         findReferences(model, refs);
 
@@ -58,10 +59,10 @@ private void buildSchemaReferenceMap(JsonNode model, JsonNode models, Map<String
 
             JsonNode subSchema = getSchema(schemaName, models);
 
-            // replace reference values with inline definitions
-            replaceRef((ObjectNode) refs.get(ref), schemaName);
+            // replace reference values with external definitions
+            replaceRef(apiId, (ObjectNode) refs.get(ref), schemaName);
 
-            buildSchemaReferenceMap(subSchema, models, modelMap);
+            buildSchemaReferenceMap(apiId, subSchema, models, modelMap);
 
             modelMap.put(schemaName, serializeExisting(subSchema));
         }
@@ -71,12 +72,10 @@ private JsonNode getSchema(String schemaName, JsonNode models) {
         return models.findPath(schemaName);
     }
 
-    private String getFlattened(JsonNode model, JsonNode models) {
+    private String getFlattened(String apiId, JsonNode model, JsonNode models) {
         HashMap<String, String> schemaMap = new HashMap<>();
 
-        buildSchemaReferenceMap(model, models, schemaMap);
-
-        replaceRefs(model, schemaMap);
+        buildSchemaReferenceMap(apiId, model, models, schemaMap);
 
         if (LOG.isTraceEnabled()) {
             try {
@@ -108,26 +107,12 @@ private void validate(JsonNode rootNode) {
         }
     }
 
-    /*
-     * Add schema references as inline definitions to the root schema
-     */
-    private void replaceRefs(JsonNode root, HashMap<String, String> schemaMap) {
-
-        ObjectNode definitionsNode = new ObjectNode(JsonNodeFactory.instance);
-
-        for (Map.Entry<String, String> entry : schemaMap.entrySet()) {
-            JsonNode schemaNode = deserialize(entry.getValue());
-            definitionsNode.set(entry.getKey(), schemaNode);
-        }
-
-        ((ObjectNode)root).set("definitions", definitionsNode);
-    }
-
     /*
      * Replace a reference node with an inline reference
      */
-    private void replaceRef(ObjectNode parent, String schemaName) {
-        parent.set("$ref", new TextNode("#/definitions/" + schemaName));
+    private void replaceRef(String apiId, ObjectNode parent, String schemaName) {
+//        parent.set("$ref", new TextNode("#/definitions/" + schemaName));
+        parent.set("$ref", new TextNode("https://apigateway.amazonaws.com/restapis/" + apiId + "/models/" + schemaName));
     }
 
     /*
@@ -163,7 +148,7 @@ JsonNode deserialize(String schemaText) {
      */
     private String serializeExisting(JsonNode root) {
         try {
-            return new ObjectMapper().writeValueAsString(root);
+            return new ObjectMapper().writerWithDefaultPrettyPrinter().writeValueAsString(root);
         } catch (JsonProcessingException e) {
             throw new IllegalStateException("Could not serialize generated schema json", e);
         }
diff --git a/src/com/amazonaws/service/apigateway/importer/impl/sdk/ApiGatewaySdkSwaggerApiImporter.java b/src/com/amazonaws/service/apigateway/importer/impl/sdk/ApiGatewaySdkSwaggerApiImporter.java
index 61c9139..b09da77 100644
--- a/src/com/amazonaws/service/apigateway/importer/impl/sdk/ApiGatewaySdkSwaggerApiImporter.java
+++ b/src/com/amazonaws/service/apigateway/importer/impl/sdk/ApiGatewaySdkSwaggerApiImporter.java
@@ -113,13 +113,13 @@ private void createModels(RestApi api, Map<String, com.wordnik.swagger.models.Mo
     private void createModel(RestApi api, String modelName, com.wordnik.swagger.models.Model model, Map<String, com.wordnik.swagger.models.Model> definitions, String modelContentType) {
         LOG.info(format("Creating model for api id %s with name %s", api.getId(), modelName));
 
-        createModel(api, modelName, model.getDescription(), generateSchema(model, modelName, definitions), modelContentType);
+        createModel(api, modelName, model.getDescription(), generateSchema(api, model, modelName, definitions), modelContentType);
     }
 
     private void createModel(RestApi api, String modelName, Property model, String modelContentType) {
         LOG.info(format("Creating model for api id %s with name %s", api.getId(), modelName));
 
-        createModel(api, modelName, model.getDescription(), generateSchema(model, modelName, swagger.getDefinitions()), modelContentType);
+        createModel(api, modelName, model.getDescription(), generateSchema(api, model, modelName, swagger.getDefinitions()), modelContentType);
     }
 
     private void updateMethods(RestApi api, String basePath, Map<String, Path> paths, List<String> apiProduces) {
@@ -320,17 +320,17 @@ private Boolean isApiKeyRequired(Operation op) {
         return false;
     }
 
-    private String generateSchema(Property model, String modelName, Map<String, com.wordnik.swagger.models.Model> definitions) {
-        return generateSchemaString(model, modelName, definitions);
+    private String generateSchema(RestApi api, Property model, String modelName, Map<String, com.wordnik.swagger.models.Model> definitions) {
+        return generateSchemaString(api, model, modelName, definitions);
     }
 
-    private String generateSchemaString(Object model, String modelName, Map<String, com.wordnik.swagger.models.Model> definitions) {
+    private String generateSchemaString(RestApi api, Object model, String modelName, Map<String, com.wordnik.swagger.models.Model> definitions) {
         try {
             String modelSchema = Json.mapper().writeValueAsString(model);
             String models = Json.mapper().writeValueAsString(definitions);
 
             // inline all references
-            String schema = new SchemaTransformer().flatten(modelSchema, models);
+            String schema = new SchemaTransformer().flatten(api.getId(), modelSchema, models);
 
             LOG.info("Generated json-schema for model " + modelName + ": " + schema);
 
@@ -340,8 +340,8 @@ private String generateSchemaString(Object model, String modelName, Map<String,
         }
     }
 
-    private String generateSchema(com.wordnik.swagger.models.Model model, String modelName, Map<String, com.wordnik.swagger.models.Model> definitions) {
-        return generateSchemaString(model, modelName, definitions);
+    private String generateSchema(RestApi api, com.wordnik.swagger.models.Model model, String modelName, Map<String, com.wordnik.swagger.models.Model> definitions) {
+        return generateSchemaString(api, model, modelName, definitions);
     }
 
     private Optional<String> getInputModel(BodyParameter p) {
@@ -400,7 +400,7 @@ private void updateModels(RestApi api, Map<String, com.wordnik.swagger.models.Mo
 
     private void updateModel(RestApi api, String modelName, com.wordnik.swagger.models.Model model) {
         LOG.info(format("Updating model for api id %s and model name %s", api.getId(), modelName));
-        updateModel(api, modelName, generateSchema(model, modelName, swagger.getDefinitions()));
+        updateModel(api, modelName, generateSchema(api, model, modelName, swagger.getDefinitions()));
     }
 
     private void updateMethod(RestApi api, Resource resource, String httpMethod, Operation op, String modelContentType) {