1 files changed, 4 insertions, 2 deletions
diff --git a/src/PJ_wink1.c b/src/PJ_wink1.c
index f64f97d2..10392fe9 100644
--- a/src/PJ_wink1.c
+++ b/src/PJ_wink1.c
@@ -1,6 +1,9 @@
 #define PJ_LIB__
-#include "projects.h"
+
 #include <errno.h>
+#include <math.h>
+
+#include "projects.h"
 
 PROJ_HEAD(wink1, "Winkel I") "\n\tPCyl., Sph.\n\tlat_ts=";
 
@@ -39,4 +42,3 @@ PJ *PROJECTION(wink1) {
 
     return P;
 }
-