1. Analytical Working Group of the International Fragrance Association (IFRA), Square Marie-Louise 49, B-1000 Brussels, Belgium; Firmenich S.A., P.O. Box 239, CH-1211 Geneva 8, Switzerland; Robertet S.A., B.P. 52100, F-06131 Grasse Cedex, France; Ets V. Mane et fils, F-06620 Le Bar sur Loup, France; and Symrise, P.O. Box 1761, D-38112 Braunschweig, Germany