diff --git a/src/special_math.hpp b/src/special_math.hpp
index ccff170..19e1414 100644
--- a/src/special_math.hpp
+++ b/src/special_math.hpp
@@ -9,7 +9,7 @@
 #ifndef __COSMOTOOL_SPECIAL_MATH_HPP
 #define __COSMOTOOL_SPECIAL_MATH_HPP
 
-#include <CosmoTool/algo.hpp>
+#include "algo.hpp"
 #include <boost/math/constants/constants.hpp>
 #include <boost/math/tools/rational.hpp>
 #include <cmath>
@@ -228,4 +228,4 @@ template <typename T> T log_modified_bessel_first_kind(T const v, T const z) {
 
 } // namespace CosmoTool
 
-#endif
\ No newline at end of file
+#endif