1 files changed, 4 insertions, 2 deletions
diff --git a/src/PJ_wink2.c b/src/PJ_wink2.c
index d715074e..d02ca567 100644
--- a/src/PJ_wink2.c
+++ b/src/PJ_wink2.c
@@ -1,6 +1,9 @@
 #define PJ_LIB__
-#include "projects.h"
+
 #include <errno.h>
+#include <math.h>
+
+#include "projects.h"
 
 PROJ_HEAD(wink2, "Winkel II") "\n\tPCyl., Sph., no inv.\n\tlat_1=";
 
@@ -47,4 +50,3 @@ PJ *PROJECTION(wink2) {
 
     return P;
 }
-