diff --git a/content/3.defense-systems/abih.md b/content/3.defense-systems/abih.md
index 846a92719981031795b30667d6cf1253bbc3fcbb..360521d04267a205a855b53f8eb157330d77aea6 100644
--- a/content/3.defense-systems/abih.md
+++ b/content/3.defense-systems/abih.md
@@ -20,7 +20,7 @@ relevantAbstracts:
 # AbiH
 
 ## Description
-AbiH a system discovered in 1996 :ref{doi10.1111/j.1574-6968.1996.tb08446.x}.
+AbiH a system discovered in 1996 :ref{doi=10.1111/j.1574-6968.1996.tb08446.x}.
 
 AbiH is one of the so-called "Abi" systems for "Abortive infection" discovered in the 90's in research related to the dairy industry :ref{doi=10.1016/j.mib.2005.06.006}. Even though, their name correspond to abortive infection, their mechanism of action does not necessarily correspond to an abortive infection.