Deceased authors, acknowledgment

The author acknowledges the contribution of his coworkers, as cited in the references. In particular, thanks are due to Antonello Filippi and Anna Giardini and her group for their contribution to the continuing work in the field of gaseous chiral clusters. Special acknowledgements are addressed to his recently deceased advisor, Fulvio Cacace, for his tireless support and encouragement. 

The author wishes to acknowledge the assistance of Frank D. Galla-way, District Engineer (deceased) and appreciated his confidence that all organizations could accomplish their tasks within the needed time frame. We wish also to thank especially Bob M. Gallaway, Texas Transportation Institute, and H. L. Fike and J. O. Izatt, The Sulphur Institute, for their contributions. 

The authors would like to acknowledgment the contribution of Dr. Bruce Hartmann, now deceased, who was the author of the chapter on acoustical properties published in the previous edition of this handbook. Dr Hartmann s comprehensive work provided the starting point for this article. 

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