“…The usefulness of reference materials (RM's) for accuracy transfer, method validation, technology transfer, and quality control monitoring has been well established (1)(2)(3). Several agencies routinely produce RM's including the National Bureau of Standards (NBS), Community Bureau of Reference (BCR), the International Atomic Energy Agency (IAEA), Agriculture Canada, the National Research Council of Canada, and the National Institute for Environmental Studies (NIES).…”