1. Why the world is grey;Andrew;Grey Systems: Theory and Application,2011
2. Book reviews: Grey systems: theory and applications;Hipel;Grey Systems: Theory and Application,2011
3. Cybernetics and systems, from past to future;Vallee;In: Proceedings of the Joint Conference of WOSC and IIGSS, Pittsburgh, Pennsylvania, PA, 2002
4. Book reviews: grey information: theory and practical applications [J];Vallee;Kybernetes,2008