diff --git a/include/CMakeLists.txt b/include/CMakeLists.txt
index 39d7869..de483df 100644
--- a/include/CMakeLists.txt
+++ b/include/CMakeLists.txt
@@ -26,13 +26,17 @@
 # either expressed or implied, of the FreeBSD Project.
 
 set(HEADERS
+    BaseFilter.h
+    BaseFilter.tpp
     BilinearTransform.h
     Butterworth.h
     Butterworth.tpp
+    differentiators.h
     difi
     DigitalFilter.h
     GenericFilter.h
     GenericFilter.tpp
+    math_utils.h
     MovingAverage.h
     polynome_functions.h
     type_checks.h
diff --git a/include/difi b/include/difi
index 016cc65..909ebaa 100644
--- a/include/difi
+++ b/include/difi
@@ -32,6 +32,7 @@
 #include "DigitalFilter.h"
 #include "GenericFilter.h"
 #include "MovingAverage.h"
+#include "differentiators.h"
 #include "polynome_functions.h"
 #include "typedefs.h"
 
diff --git a/tests/diffTesters.h b/tests/diffTesters.h
index f53dcbf..0a65fb0 100644
--- a/tests/diffTesters.h
+++ b/tests/diffTesters.h
@@ -27,7 +27,6 @@
 
 #pragma once
 #include "catch_helper.h"
-#include "differentiators.h"
 #include "difi"
 #include <array>
 #include <catch2/catch.hpp>