Makefile

--- a/Makefile	Tue Mar 22 08:32:22 1994 +0100
+++ b/Makefile	Tue Mar 22 18:07:45 1994 +0100
@@ -23,6 +23,7 @@
 	prod.thy prod.ML sum.thy sum.ML wf.thy wf.ML \
 	mono.ML lfp.thy lfp.ML gfp.thy gfp.ML nat.thy nat.ML sexp.thy \
 	sexp.ML univ.thy univ.ML llist.thy llist.ML list.thy list.ML \
+	datatype.ML \
 	../Provers/classical.ML ../Provers/simplifier.ML \
 	../Provers/splitter.ML ../Provers/ind.ML