(Dieter Nuetzel) fix typo in help screen
diff --git a/progs/demos/ipers.c b/progs/demos/ipers.c
index 8168034..d43c662 100644
--- a/progs/demos/ipers.c
+++ b/progs/demos/ipers.c
@@ -357,7 +357,7 @@
    printstring(GLUT_BITMAP_TIMES_ROMAN_24, "p - Toggle Wire frame");
    glRasterPos2i(60, 150);
    printstring(GLUT_BITMAP_TIMES_ROMAN_24,
-	       "b - Toggle GL_EXT_rescale_normal extension");
+	       "n - Toggle GL_EXT_rescale_normal extension");
    glRasterPos2i(60, 120);
    printstring(GLUT_BITMAP_TIMES_ROMAN_24,
 	       "+/- - Increase/decrease the Object maximum LOD");