diff --git a/src/lsa.hpp b/src/lsa.hpp
index 7272aed..3d453d2 100644
--- a/src/lsa.hpp
+++ b/src/lsa.hpp
@@ -284,7 +284,7 @@
   }
 
   bool
-  isEqualContent(AdjLsa& alsa);
+  isEqualContent(const AdjLsa& alsa) const;
 
   /*! \brief Installs this LSA's name prefixes into the NPT.
 
@@ -384,7 +384,7 @@
   }
 
   bool
-  isEqualContent(const CoordinateLsa& clsa);
+  isEqualContent(const CoordinateLsa& clsa) const;
 
   void
   writeLog() const override;