Updated MOD reference

--- a/doc-src/Inductive/ind-defs.bbl	Wed Jan 21 15:50:25 1998 +0100
+++ b/doc-src/Inductive/ind-defs.bbl	Fri Jan 23 13:47:37 1998 +0100
@@ -161,8 +161,7 @@
 \newblock Tool support for logics of programs,
 \newblock In {\em Mathematical Methods in Program Development: Summer School
   Marktoberdorf 1996}, M.~Broy, Ed., NATO ASI Series F. Springer, Published
-  1997,
-\newblock In press
+  1997, pp.~461--498
 
 \bibitem{paulson-gr}
 Paulson, L.~C., Gr\c{a}bczewski, K.,