diff --git a/src/types/map.ts b/src/types/map.ts
index 9acbc91..8a198c1 100644
--- a/src/types/map.ts
+++ b/src/types/map.ts
@@ -15,6 +15,8 @@ import { PropSchema, AdditionalPropArgs } from "../api/types";
  * This can be both plain objects (default) or ES6 Map like structures.
  * This will be inferred from the initial value of the targetted attribute.
  *
+ * For `Map`s which are not string-keyed, check out `mapAsArray`.
+ *
  * @param additionalArgs optional object that contains beforeDeserialize and/or afterDeserialize handlers
  */
 export default function map(