diff --git a/src/type/schema.d.ts b/src/type/schema.d.ts
index e0d7441dba2..c4917564516 100644
--- a/src/type/schema.d.ts
+++ b/src/type/schema.d.ts
@@ -2,7 +2,7 @@
 /* eslint-disable import/no-cycle */
 
 import { Maybe } from '../jsutils/Maybe';
-import { ObjMap } from '../jsutils/ObjMap';
+import { ObjMap, ReadOnlyObjMap, ReadOnlyObjMapLike } from '../jsutils/ObjMap';
 
 import { SchemaDefinitionNode, SchemaExtensionNode } from '../language/ast';