Reference test method for release of nickel from products intended to come into direct and prolonged contact with the skin; German version EN 1811:1998+A1:2008— 19 стр.
39.060 Jewellery. Including precious metals, precious and semi-precious stones / Ювелирное дело. Включая драгоценные металлы, драгоценные и полудрагоценные камни