1. O. Bayer, Angewandte Chemie, 1947, 59, 257.

2. Personal discussion with Angela Austin of IAL Consultants, 2003.

3. E. Grigat and D. Dieterich in Polyurethane Handbook, 2nd Edition, Ed., G. Oertel, Hanser Publishers, New York, NY, USA, 1993, p.12.

4. J.M. Hugo, M.W. Spence and T.D. Lickly, Proceedings of the Polyurethane Foam Association Technical Program, Williamsburg, Virginia, USA, October 1997, Paper No.10.

5. R.E. Stevens, G.P. Dado, M.J. Kimock and M.L. Listemann, Proceedings of the SPI Polyurethenes World Congress, Amsterdam, The Netherlands, 1997, p.118.

6. M.L. Listemann, A.C. Savoca and A.L. Wressell, Proceedings of the SPI Polyurethanes World Congress, Nice, France, 1991, p.524.

7. L.F. Lawler and R. Schiffauer, Proceedings of the SPI Polyurethanes World Congress, Vancouver, BC, Canada, 1993, p.288.

8. E. Cassidy, P. Chaffanjon and R. Lockwood, Proceedings of the SPI Polyurethanes World Congress, Amsterdam, The Netherlands, 1997, p.55.

9. A. Parfondry in The Polyurethanes Book, Ed. D. Randall and S. Lee, John Wiley & Sons, New York, NY, USA, 2002, Chapter 14, p.221.

10. W. Hahn in Polyurethane Handbook, 2nd Edition, Ed., G. Oertel, Hanser Publishers, New York, NY, USA, 1993, p.23.

11. Joint Industry Foam Standards and Guidelines, Section 15, Glossary of Flexible Polyurethane Technology, Polyurethane Foam Association, Knoxville, TN, USA, 1994.

12. J.M. Monso, J. Soler, P. Escobar and C. Fernandez-Llamazares, Proceedings of UTECH 94 Conference, The Hague, The Netherlands, 1994, Paper No.47.

13. B. Kanner and T. Decker,