Armando Francesco Borghesani Associate Professor of Physics Department of Physics University of Padua Italy After his degree ``Laurea in Fisica'' from University of Padua in March 1979, Dr Borghesani worked as junior scientist in the R&D labs of SGS-ATES (now ST Microelectronics, Milan, Italy) in the field of plasma etching of semiconductors. He then joined ASSORENI (now Eniricerche, Milan, Italy), the company for the scientific research of the ENI Group, after which he got a tenured position as Assistant Professor in the Low Temperature Lab of the Department of Physics of the University of Padua. In 1992 he was promoted Associate Professor of Physics at the same university. He has taught courses in Electromagnetism, Fundamentals of Quantum Mechanics, and Analog Electronics.
The field of electrons and ions in liquid helium has reached maturity and efforts in this field will continue. This is an appropriate time for a comprehensive archival review. It will serve scholars and new workers in the field well. I approve of the organization of this book and all topics I am aware of appear to be covered. Arnold Dahm, Case Western Reserve University, Cleveland Of very high quality, well-written, providing a thorough coverage of the subject. Peter McClintock, University of Lancaster