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Acknowledgements
A big thank you goes to the publisher (Springer Science+Business Media, LLC,
233 Spring Street, New York, NY 10013, USA), for promptness and cordiality they
provide to their authors.
Finally, we wish to deeply thank our parents, for the encouragement and love with
which they have surrounded us during all these years.
Asansol, India
2020
Dr. Puja Dey
Prof. Jitendra Nath Roy