diff --git a/keywords.go b/keywords.go
index 943ee42..92d6dd3 100644
--- a/keywords.go
+++ b/keywords.go
@@ -60,7 +60,7 @@ func NewType() Validator {
 	return &Type{}
 }
 
-// FirstValue returns the first element in the values of this type.
+// String returns the type(s) as a string, or unknown if there is no known type.
 func (t Type) String() string {
 	if len(t.vals) == 0 {
 		return "unknown"
diff --git a/schema.go b/schema.go
index 92804f6..e7c9f75 100644
--- a/schema.go
+++ b/schema.go
@@ -50,12 +50,8 @@ type RootSchema struct {
 
 // TopLevelType returns a string representing the schema's top-level type.
 func (rs *RootSchema) TopLevelType() string {
-	validator, ok := rs.Schema.Validators["type"]
-	if ok {
-		typeValidator, ok := validator.(*Type)
-		if ok {
-			return typeValidator.String()
-		}
+	if t, ok := rs.Schema.Validators["type"].(*Type); ok {
+		return t.String()
 	}
 	return "unknown"
 }
diff --git a/schema_test.go b/schema_test.go
index 1429ef9..d020cce 100644
--- a/schema_test.go
+++ b/schema_test.go
@@ -110,6 +110,18 @@ func TestTopLevelType(t *testing.T) {
 	if rs.TopLevelType() != "array" {
 		t.Errorf("error: schemaArray should be an array")
 	}
+
+	schemaUnknown := []byte(`{
+    "title": "Typeless",
+    "items" : { "title" : "REFERENCE", "$ref" : "#" }
+}`)
+	rs = &RootSchema{}
+	if err := json.Unmarshal(schemaUnknown, rs); err != nil {
+		panic("unmarshal schema: " + err.Error())
+	}
+	if rs.TopLevelType() != "unknown" {
+		t.Errorf("error: schemaUnknown should have unknown type")
+	}
 }
 
 func TestMust(t *testing.T) {