diff --git a/go.mod b/go.mod
index 5fbd1f88a..4e9ff5813 100644
--- a/go.mod
+++ b/go.mod
@@ -8,3 +8,5 @@ require (
 	gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127 // indirect
 	gopkg.in/yaml.v2 v2.2.2 // indirect
 )
+
+go 1.13
diff --git a/openapi3/swagger_utils.go b/openapi3/swagger_utils.go
index 983bdc207..0877982b4 100644
--- a/openapi3/swagger_utils.go
+++ b/openapi3/swagger_utils.go
@@ -25,10 +25,15 @@ func clearResolvedExternalRef(rr RefOrValue) {
 // ClearResolvedExternalRefs Recursively iterate over the swagger structure, resetting <Type>Ref structs where
 // the reference is remote and was resolved
 func ClearResolvedExternalRefs(swagger *Swagger) {
-	resetExternalRef(reflect.ValueOf(swagger))
+	visited := map[reflect.Value]struct{}{}
+	resetExternalRef(reflect.ValueOf(swagger), visited)
 }
 
-func resetExternalRef(c reflect.Value) {
+func resetExternalRef(c reflect.Value, visited map[reflect.Value]struct{}) {
+	if _, ok := visited[c]; ok {
+		return
+	}
+	visited[c] = struct{}{}
 	switch c.Kind() {
 	// If it is a struct, check if it's the desired type first before drilling into fields
 	// Further if this is a <Type>Ref struct, reset the reference if it's remote and resolved
@@ -39,28 +44,28 @@ func resetExternalRef(c reflect.Value) {
 				clearResolvedExternalRef(rov)
 			}
 		}
-		for i := 0; i < c.NumField(); i += 1 {
-			resetExternalRef(c.Field(i))
+		for i := 0; i < c.NumField(); i++ {
+			resetExternalRef(c.Field(i), visited)
 		}
 
 	// If it is a pointer or interface we need to unwrap and call once again
 	case reflect.Interface, reflect.Ptr:
 		c2 := c.Elem()
 		if c2.IsValid() {
-			resetExternalRef(c2)
+			resetExternalRef(c2, visited)
 		}
 
 	// If it is a slice we iterate over each each element
 	case reflect.Slice:
-		for i := 0; i < c.Len(); i += 1 {
-			resetExternalRef(c.Index(i))
+		for i := 0; i < c.Len(); i++ {
+			resetExternalRef(c.Index(i), visited)
 		}
 
 	// If it is a map we iterate over each of the key,value pairs
 	case reflect.Map:
 		mi := c.MapRange()
 		for mi.Next() {
-			resetExternalRef(mi.Value())
+			resetExternalRef(mi.Value(), visited)
 		}
 
 	// And everything else will simply be ignored
diff --git a/openapi3/swagger_utils_test.go b/openapi3/swagger_utils_test.go
index d3c56c879..0a3963a9f 100644
--- a/openapi3/swagger_utils_test.go
+++ b/openapi3/swagger_utils_test.go
@@ -24,7 +24,8 @@ func TestResettingExternalRefs(t *testing.T) {
 
 	openapi3.ClearResolvedExternalRefs(doc)
 
-	for _, s := range []string{"ref1", "ref2", "ref3", "ref4", "ref5", "ref6"} {
+	fields := []string{"ref1", "ref2", "ref3", "ref4", "ref5", "ref6", "ref7", "ref8", "ref9"}
+	for _, s := range fields {
 		sr := doc.Components.Schemas["AnotherTestSchema"].Value.Properties[s]
 		require.True(t, sr.IsValue())
 		require.False(t, sr.Resolved())
diff --git a/openapi3/testdata/components.openapi.yml b/openapi3/testdata/components.openapi.yml
index 6c307423b..3d89390d0 100644
--- a/openapi3/testdata/components.openapi.yml
+++ b/openapi3/testdata/components.openapi.yml
@@ -10,6 +10,12 @@ components:
       type: string
     CustomTestSchema:
       "$ref": "#/components/schemas/Name"
+    GraphTestSchema:
+      properties:
+        children:
+          type: array
+          items: 
+            "$ref": "#/components/schemas/GraphTestSchema"
   responses:
     Name:
       description: description
diff --git a/openapi3/testdata/test.refcache.openapi.yml b/openapi3/testdata/test.refcache.openapi.yml
index da7a4f97d..bcf0d480d 100644
--- a/openapi3/testdata/test.refcache.openapi.yml
+++ b/openapi3/testdata/test.refcache.openapi.yml
@@ -25,3 +25,6 @@ components:
           "$ref": http://localhost:7965/components3.openapi.yml#/components/schemas/NestedRefToComp2Schema
         ref8:
           "$ref": http://localhost:7965/components.openapi.yml#/components/schemas/CustomTestSchema
+        ref9:
+          "$ref": http://localhost:7965/components.openapi.yml#/components/schemas/GraphTestSchema
+