--- ray/src/px/ra_bn.c	1992/09/21 12:14:44	2.3
+++ ray/src/px/ra_bn.c	1992/10/02 16:24:56	2.4
@@ -16,11 +16,11 @@ static char SCCSid[] = "$SunId$ LBL";
 #include  <fcntl.h>
 #endif
 
+#include  <math.h>
+
 #include  "color.h"
 
 #include  "resolu.h"
-
-extern double  pow();
 
 extern char  *malloc();