Acknowledgements

This report is based on the work of several years, during which I have had the opportunity to interact, directly or indirectly, with a large variety of persons, most of them physicists of all ages and of many nationalities, but also mathematicians, statisticians and metrologists. In particular, the interest shown by those who attended the lectures, and also the criticisms of those who had strong prejudices towards the approach I was presenting, has been highly stimulating. I take this opportunity to thank them all.

Special acknowledgements go to Romano Scozzafava of ``La Sapienza'' for many discussions about the fundamental aspects of probability theory. The many clarifications about DIN and ISO recommandations received by Klaus Weise of the PTB Braunschweig (Germany) have been particulary usefull. I would like to thank Fritz Fröhner, Frank Lad of Canterbury University (New Zealand), Gianni Penso of ``La Sapienza'', Stefan Schlenstedt of Zeuten (Germany), Pia Astone and Mirko Raso of INFN Roma1 for critical comments on the manuscript, as well on the on the old version of the primer. Finally I would like to thank Bruno Pellizzoni of INFN Roma1 for technical support with many of the drawings.