(a) aggregation, for the purpose of acquiring and retaining the right to benefit and of calculating the amount of benefit, of all periods taken into account under the laws of the several countries;
(a) go gcomhshuimeofar, d'fhonn an ceart chun sochair a fháil agus a choinneáil agus méid an tsochair a ríomh, na tréimhsi uile a chu i near san áireamh faoi dhlíthe na dtiortha éagsúla;