diff --git a/fps/FPS_log.hpp b/fps/FPS_log.hpp
index 79fca6a..93f505a 100644
--- a/fps/FPS_log.hpp
+++ b/fps/FPS_log.hpp
@@ -2,6 +2,7 @@
 #include <vector>
 #include "../fps/FPS_differetial.hpp"
 #include "../fps/FPS_integral.hpp"
+#include "../fps/FPS_inv.hpp"
 
 namespace po167{
 template<class T>