Artikel 35

1. In the event of an aggravation of any invalidity for which a person is receiving benefits under the legislation of one Contracting Party only, the following provisions shall apply:
(a) if the person concerned, since he began to receive benefits, has not been subject to the legislation of any other Contracting Party, the competent institution of the first Party shall be bound to award benefits, taking the aggravation into account, in accordance with the provisions of the legislation which that institution applies;
(b) if the person concerned, since he began to receive benefits, has been subject to the legislation of one or more other Contracting Parties, benefits shall be awarded, taking the aggravation into account, in accordance with the provisions of Articles 28 to 34;
(c) in the case referred to in the preceding sub-paragraph, the date on which the aggravation was established shall be regarded as the date on which the contingency arose;
(d) if in the case referred to in sub-paragraph (b) of this paragraph the person concerned is not entitled to benefits from the institution of another Contracting Party, the competent institution of the first Party shall be bound to award benefits, taking the aggravation into account, in accordance with the provisions of the legislation which that institution applies.
2. In the event of an aggravation of any invalidity for which a person is receiving benefits under the legislation of two or more Contracting Parties/benefits shall be awarded, taking the aggravation into account, in accordance with the provisions of Articles 28 to 34. The provisions of sub-paragraph (c) of the preceding paragraph shall apply, mutatis mutandis.