Artikel 19

1. Where the legislation of a Contracting Party makes the acquisition, maintenance or recovery of the entitlement to benefits conditional upon the completion of periods of insurance, the competent institution of that Party shall, to that end, for the purpose of adding periods together, take account, to the extent necessary, of periods of insurance completed under the legislation of any other Contracting Party and, where appropriate, of periods of residence completed after the age of sixteen under non-contributory schemes of any other Contracting Party, as if they were periods of insurance completed under the legislation of the first Party.
2. Where the legislation of a Contracting Party makes admission to compulsory insurance conditional upon the completion of periods of insurance, periods of insurance completed under the legislation of any other Contracting Party and, where appropriate, periods of residence completed after the age of sixteen under the non-contributory schemes of any other Contracting Party shall, to that end, for the purpose of adding periods together, be taken into account, to the extent necessary, as if they were periods of insurance completed under the legislation of the first Party.