Artikel 57

Where the legislation of a Contracting Party makes the entitlement to benefits conditional upon the completion of periods of employment, occupational activity or residence, the institution which applies that legislation shall, to that end, for the purpose of adding periods together, take account, to the extent necessary, of periods of employment, occupational activity or residence completed under the legislation of any other Contracting Party, as if they were periods of employment, occupational activity or residence completed under the legislation of the first Party.