1 files changed, 1 insertions, 1 deletions
diff --git a/src/deriv.cpp b/src/deriv.cpp
index 3839809e..bc7fa19e 100644
--- a/src/deriv.cpp
+++ b/src/deriv.cpp
@@ -4,7 +4,7 @@
 #include <math.h>
 
 #include "proj.h"
-#include "projects.h"
+#include "proj_internal.h"
 
 int pj_deriv(PJ_LP lp, double h, const PJ *P, struct DERIVS *der) {
     PJ_XY t;