This author has not been identified. It may be one of the following persons: Look up 'Alberto Gonzalez-Sanchez' in GoogleThis author has not been identified. It may be one of the following persons: Look up 'Eric Piel' in GoogleThis author has not been identified. It may be one of the following persons: Look up 'Hans-Gerhard Gross' in GoogleThis author has not been identified. Look up 'Arjan J. C. van Gemund' in Google