Updated comments.

--- a/src/FOL/intprover.ML	Thu Apr 06 11:02:55 1995 +0200
+++ b/src/FOL/intprover.ML	Thu Apr 06 11:04:37 1995 +0200
@@ -11,7 +11,9 @@
 
 Roy Dyckhoff.
 Contraction-Free Sequent Calculi for Intuitionistic Logic.
-J. Symbolic Logic (in press)
+J. Symbolic Logic  57(3), 1992, pages 795-807.
+
+The approach was developed independently by Roy Dyckhoff and L C Paulson.
 *)
 
 signature INT_PROVER =