diff --git a/binding/binding_test.go b/binding/binding_test.go
index 806f3ac9..cfafb83a 100644
--- a/binding/binding_test.go
+++ b/binding/binding_test.go
@@ -1177,6 +1177,20 @@ func testBodyBindingFail(t *testing.T, b Binding, name, path, badPath, body, bad
 	assert.Error(t, err)
 }
 
+type Identifier struct {
+	Assigner *Reference `json:"assigner,omitempty"`
+}
+
+type Reference struct {
+	Identifier *Identifier `json:"identifier,omitempty"`
+}
+
+func TestLoopReference(t *testing.T) {
+	r := Reference{}
+	err := mapForm(&r, map[string][]string{})
+	assert.Error(t, err)
+}
+
 func testProtoBodyBinding(t *testing.T, b Binding, name, path, badPath, body, badBody string) {
 	assert.Equal(t, name, b.Name())
 
diff --git a/binding/form_mapping.go b/binding/form_mapping.go
index c4543f9a..48db75c2 100644
--- a/binding/form_mapping.go
+++ b/binding/form_mapping.go
@@ -18,6 +18,7 @@ import (
 var LimitMappingCallNumber = 10000
 
 var errUnknownType = errors.New("Unknown type")
+var ErrMaybeCircularReference = errors.New("Maybe entering a circular reference")
 
 func mapUri(ptr interface{}, m map[string][]string) error {
 	return mapFormByTag(ptr, m, "uri")
@@ -73,7 +74,7 @@ func mapping(value reflect.Value, field reflect.StructField, setter setter, tag
 	}
 
 	if callNumber > LimitMappingCallNumber {
-		return false, errors.New("Maybe entering a circular reference")
+		return false, ErrMaybeCircularReference
 	}
 
 	if vKind != reflect.Struct || !field.Anonymous {
diff --git a/binding/form_mapping_test.go b/binding/form_mapping_test.go
index c9d6111b..04145c21 100644
--- a/binding/form_mapping_test.go
+++ b/binding/form_mapping_test.go
@@ -52,7 +52,7 @@ func TestMappingBaseTypes(t *testing.T) {
 
 		field := val.Elem().Type().Field(0)
 
-		_, err := mapping(val, emptyField, formSource{field.Name: {tt.form}}, "form")
+		_, err := mapping(val, emptyField, formSource{field.Name: {tt.form}}, "form", 0)
 		assert.NoError(t, err, testName)
 
 		actual := val.Elem().Field(0).Interface()