diff --git a/docs/images/Makefile b/docs/images/Makefile
index fc8352ceeb9301fe960b0aecfbb0dbead8c6a6e3..2bc794e965ba7be048c00263d49e6a8c0769a5b5 100644
--- a/docs/images/Makefile
+++ b/docs/images/Makefile
@@ -1,5 +1,5 @@
 
-MERKLE_DAG = swh-merkle-dag.svg
+MERKLE_DAG =  swh-merkle-dag.pdf swh-merkle-dag.svg
 
 BUILD_TARGETS =
 BUILD_TARGETS += $(MERKLE_DAG)