Smjernice OECD-a o transfernim cijenama iz 2010., točka 9.23.
The services provided include fulfilment and logistics services; customer support services; accountancy, tax, legal, human resources, localisation and similar back office services; merchandising and marketing support services; and purchasing assistance.“ Dostupné na tejto adrese: https://publications.parliament.uk/pa/cm201213/cmselect/cmpubacc/writev/716/m03.htm.