diff --git a/test/rustint/core_test.clj b/test/rustint/core_test.clj
index 4281be5..b8e34d7 100644
--- a/test/rustint/core_test.clj
+++ b/test/rustint/core_test.clj
@@ -182,6 +182,12 @@
   )
 )
 
+(deftest identificador-test04
+  (testing "Test 04 identificador"
+    (is (= (identificador? '12e0) false))
+  )
+)
+
 (deftest palabra-reservada-test01
   (testing "Test 01 palabra reservada"
     (is (= (palabra-reservada? 'while) true))