diff --git a/docs/refex/Makefile b/docs/refex/Makefile
index 5acfdb5138..e77c7f3580 100644
--- a/docs/refex/Makefile
+++ b/docs/refex/Makefile
@@ -37,7 +37,8 @@ OBJECTS=ex1 ex2 ex3 ex4 ex5 ex6 ex7 ex8 ex9 ex10 ex11 ex12 ex13 ex14 \
         ex28 ex29 ex30 ex31 ex32 ex33 ex34 ex35 ex36 ex37 ex38 ex39 ex40 \
         ex41 ex42 ex43 ex44 ex45 ex46 ex47 ex48 ex49 ex50 ex51 ex52 ex53 \
         ex54 ex55 ex56 ex57 ex58 ex59 ex60 ex61 ex62 ex63 ex64 ex65 ex66 \
-        ex67 ex68 ex69 ex70 ex71 ex72 ex73 ex74 ex75 ex76 ex77 ex78 ex79
+        ex67 ex68 ex69 ex70 ex71 ex72 ex73 ex74 ex75 ex76 ex77 ex78 ex79 \
+	ex80
 
 TEXOBJECTS=$(addsuffix .tex, $(OBJECTS))