diff --git a/Makefile.am b/Makefile.am
index 8e5c191..fad77d1 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -40,7 +40,7 @@
 		-lnl-3 \
 		-lnl-genl-3
 
-ncsi_netlink_CPPFLAGS = -isystem=/usr/include/libnl3
+ncsi_netlink_CPPFLAGS = -isystem /usr/include/libnl3
 ncsi_netlink_CXXFLAGS = -flto