diff --git a/apk_frauder/src/main.rs b/apk_frauder/src/main.rs
index 3750ed9..edcec4b 100644
--- a/apk_frauder/src/main.rs
+++ b/apk_frauder/src/main.rs
@@ -34,7 +34,9 @@ struct FileHeader {
     external_file_attributes: u32,
     offset_local_header: u32,
     file_name: Vec<u8>,
-    extra_field: Vec<u8>, // TODO: zip64
+    extra_field: Vec<u8>, // TODO:
+    // zip64 https://github.com/python/cpython/blob/cc11c76da7a099bb4535ab8ca507e55263fc35b6/Lib/zipfile/__init__.py#L500
+    // https://pkware.cachefly.net/webdocs/casestudies/APPNOTE.TXT 4.5 Extensible data fields
     file_comment: Vec<u8>,
 }