diff --git a/hyper-schema.json b/hyper-schema.json
index b633bd50..204def3e 100644
--- a/hyper-schema.json
+++ b/hyper-schema.json
@@ -7,7 +7,7 @@
             "allOf": [
                 { "$ref": "http://json-schema.org/drafts/schema" },
                 {
-                    "items": { "$ref": "#" }
+                    "items": { "$ref": "#/definitions/subSchema" }
                 }
             ]
         },
@@ -30,7 +30,7 @@
                 },
                 "targetSchema": {
                     "description": "JSON Schema describing the link target",
-                    "allOf": [ { "$ref": "#" } ]
+                    "allOf": [ { "$ref": "#/definitions/subSchema" } ]
                 },
                 "mediaType": {
                     "description": "media type (as defined by RFC 2046) describing the link target",
@@ -47,52 +47,64 @@
                 },
                 "schema": {
                     "description": "Schema describing the data to submit along with the request",
-                    "allOf": [ { "$ref": "#" } ]
+                    "allOf": [ { "$ref": "#/definitions/subSchema" } ]
                 }
             }
+        },
+        "subSchema": {
+            "oneOf": [
+                {
+                    "allOf": [
+                        { "$ref": "#" },
+                        { "$ref": "http://json-schema.org/draft/schema#/definitions/notJsonReference" }
+                    ]
+                },
+                { "$ref": "http://json-schema.org/draft/schema#/definitions/jsonReference" }
+            ]
         }
     },
+
     "allOf": [ { "$ref": "http://json-schema.org/draft/schema#" } ],
     "properties": {
         "additionalItems": {
             "anyOf": [
                 { "type": "boolean" },
-                { "$ref": "#" }
+                { "$ref": "#/definitions/subSchema" }
             ]
         },
         "additionalProperties": {
             "anyOf": [
                 { "type": "boolean" },
-                { "$ref": "#" }
+                { "$ref": "#/definitions/subSchema" }
             ]
         },
         "dependencies": {
             "additionalProperties": {
                 "anyOf": [
-                    { "$ref": "#" },
+                    { "$ref": "#/definitions/subSchema" },
                     { "type": "array" }
                 ]
             }
         },
         "items": {
             "anyOf": [
-                { "$ref": "#" },
+                { "$ref": "#/definitions/subSchema" },
                 { "$ref": "#/definitions/schemaArray" }
             ]
         },
         "definitions": {
-            "additionalProperties": { "$ref": "#" }
+            "additionalProperties": { "$ref": "#/definitions/subSchema" }
         },
         "patternProperties": {
-            "additionalProperties": { "$ref": "#" }
+            "additionalProperties": { "$ref": "#/definitions/subSchema" }
         },
         "properties": {
-            "additionalProperties": { "$ref": "#" }
+            "additionalProperties": { "$ref": "#/definitions/subSchema" }
         },
         "allOf": { "$ref": "#/definitions/schemaArray" },
         "anyOf": { "$ref": "#/definitions/schemaArray" },
         "oneOf": { "$ref": "#/definitions/schemaArray" },
-        "not": { "$ref": "#" },
+        "not": { "$ref": "#/definitions/subSchema" },
 
         "base": {
             "description": "URI Template resolved as for the 'href' keyword in the Link Description Object.  The resulting URI Reference is resolved against the current URI base and sets the new URI base for URI references within the instance.",
diff --git a/schema.json b/schema.json
index 15502e9b..79e63af0 100644
--- a/schema.json
+++ b/schema.json
@@ -3,10 +3,25 @@
     "id": "http://json-schema.org/draft/schema#",
     "title": "Core schema meta-schema",
     "definitions": {
+        "jsonReference": {
+            "type": "object",
+            "properties": {
+                "$ref": {
+                    "type": "string",
+                    "format": "uriref"
+                }
+            },
+            "required": [ "$ref" ]
+        },
+        "notJsonReference": {
+            "not": {
+                "required": [ "$ref" ]
+            }
+        },
         "schemaArray": {
             "type": "array",
             "minItems": 1,
-            "items": { "$ref": "#" }
+            "items": { "$ref": "#/definitions/subSchema" }
         },
         "positiveInteger": {
             "type": "integer",
@@ -33,6 +48,17 @@
             "type": "array",
             "items": { "type": "string" },
             "uniqueItems": true
+        },
+        "subSchema": {
+            "oneOf": [
+                {
+                    "allOf": [
+                        { "$ref": "#" },
+                        { "$ref": "#/definitions/notJsonReference" }
+                    ]
+                },
+                { "$ref": "#/definitions/jsonReference" }
+            ]
         }
     },
     "type": ["object", "boolean"],
@@ -77,10 +103,10 @@
             "type": "string",
             "format": "regex"
         },
-        "additionalItems": { "$ref": "#" },
+        "additionalItems": { "$ref": "#/definitions/subSchema" },
         "items": {
             "anyOf": [
-                { "$ref": "#" },
+                { "$ref": "#/definitions/subSchema" },
                 { "$ref": "#/definitions/schemaArray" }
             ],
             "default": {}
@@ -95,27 +121,27 @@
         "maxProperties": { "$ref": "#/definitions/positiveInteger" },
         "minProperties": { "$ref": "#/definitions/positiveIntegerDefault0" },
         "required": { "$ref": "#/definitions/stringArray" },
-        "additionalProperties": { "$ref": "#" },
+        "additionalProperties": { "$ref": "#/definitions/subSchema" },
         "definitions": {
             "type": "object",
-            "additionalProperties": { "$ref": "#" },
+            "additionalProperties": { "$ref": "#/definitions/subSchema" },
             "default": {}
         },
         "properties": {
             "type": "object",
-            "additionalProperties": { "$ref": "#" },
+            "additionalProperties": { "$ref": "#/definitions/subSchema" },
             "default": {}
         },
         "patternProperties": {
             "type": "object",
-            "additionalProperties": { "$ref": "#" },
+            "additionalProperties": { "$ref": "#/definitions/subSchema" },
             "default": {}
         },
         "dependencies": {
             "type": "object",
             "additionalProperties": {
                 "anyOf": [
-                    { "$ref": "#" },
+                    { "$ref": "#/definitions/subSchema" },
                     { "$ref": "#/definitions/stringArray" }
                 ]
             }
@@ -142,7 +168,7 @@
         "allOf": { "$ref": "#/definitions/schemaArray" },
         "anyOf": { "$ref": "#/definitions/schemaArray" },
         "oneOf": { "$ref": "#/definitions/schemaArray" },
-        "not": { "$ref": "#" }
+        "not": { "$ref": "#/definitions/subSchema" }
     },
     "dependencies": {
         "exclusiveMaximum": [ "maximum" ],