1 files changed, 2 insertions, 0 deletions
diff --git a/_TODO.md b/_TODO.md
index 60d1fc0..2809736 100644
--- a/_TODO.md
+++ b/_TODO.md
@@ -144,6 +144,8 @@ auxiliary metadata:
   * generate PDF/A compliant PDF files
     <https://www.aalto.fi/en/services/creating-a-pdfa-compliant-file-of-your-thesis>
     <https://tex.stackexchange.com/a/655531/309738>
+  * support adding DOI to XMP metadata
+    <https://www.crossref.org/blog/marking-up-doi/>
   * maybe tweak PDF tagging
     <https://ctan.org/pkg/tagpdf>
     <https://tex.stackexchange.com/a/609329/309738>