diff --git a/book/source/01-intro.md b/book/source/01-intro.md
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--- a/book/source/01-intro.md
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@@ -1,4 +1,5 @@
 # Notes on OpenPGP
+Tammi test
 
 An introduction to the concepts of OpenPGP, aimed mainly at software
 developers who are looking to use OpenPGP functionality in their projects.