Feasibility study for the development of a toner-Reference Material, Zappa, Giovanna, Gatti Rosanna, Zoani Claudia, Carconi P., D’Alessio A., Di Bonito R., Lamberti I., and Mosiello Lucia , International workshop IMEKO TC-8 “Traceability to support CIPM MRA and other international arrangements” - 6-7 November 2008, Torino, (2008)