diff --git a/Doc/lib/libnis.tex b/Doc/lib/libnis.tex
index cc1482db565..fe4acb5d63e 100644
--- a/Doc/lib/libnis.tex
+++ b/Doc/lib/libnis.tex
@@ -2,7 +2,7 @@
          Interface to Sun's NIS (Yellow Pages)}
 
 \declaremodule{extension}{nis}
-  \platform{UNIX}
+  \platform{Unix}
 \moduleauthor{Fred Gansevles}{Fred.Gansevles@cs.utwente.nl}
 \sectionauthor{Moshe Zadka}{moshez@zadka.site.co.il}
 \modulesynopsis{Interface to Sun's NIS (Yellow Pages) library.}