diff --git a/linq/linq.d.ts b/linq/linq.d.ts
index c15bc895e4..11bf36df92 100644
--- a/linq/linq.d.ts
+++ b/linq/linq.d.ts
@@ -205,9 +205,9 @@ declare module linq {
     }
 
     interface OrderedEnumerable<T> extends Enumerable<T> {
-        ThenBy(keySelector: ($) => T): OrderedEnumerable<T>;
+        ThenBy(keySelector: ($: T) => any): OrderedEnumerable<T>;
         ThenBy(keySelector: string): OrderedEnumerable<T>;
-        ThenByDescending(keySelector: ($) => T): OrderedEnumerable<T>;
+        ThenByDescending(keySelector: ($: T) => any): OrderedEnumerable<T>;
         ThenByDescending(keySelector: string): OrderedEnumerable<T>;
     }