--- a/src/Doc/IsarRef/Preface.thy Sat Jan 26 16:10:50 2013 +0100
+++ b/src/Doc/IsarRef/Preface.thy Sat Jan 26 16:30:47 2013 +0100
@@ -17,12 +17,16 @@
theory and proof development. Compared to raw ML, the Isabelle/Isar
top-level provides a more robust and comfortable development
platform, with proper support for theory development graphs, managed
- transactions with unlimited undo etc. The Isabelle/Isar version of
- the \emph{Proof~General} user interface
- \cite{proofgeneral,Aspinall:TACAS:2000} provides a decent front-end
- for interactive theory and proof development in this advanced
- theorem proving environment, even though it is somewhat biased
- towards old-style proof scripts.
+ transactions with unlimited undo etc.
+
+ In its pioneering times, the Isabelle/Isar version of the
+ \emph{Proof~General} user interface
+ \cite{proofgeneral,Aspinall:TACAS:2000} has contributed to the
+ success of for interactive theory and proof development in this
+ advanced theorem proving environment, even though it was somewhat
+ biased towards old-style proof scripts. The more recent
+ Isabelle/jEdit Prover IDE \cite{Wenzel:2012} emphasizes the
+ document-oriented approach of Isabelle/Isar again more explicitly.
\medskip Apart from the technical advances over bare-bones ML
programming, the main purpose of the Isar language is to provide a