The time limits provided for in Article 641 are extended to twenty-four months for inheritance declarations involving real estate or real estate rights for which the deceased’s right of ownership was not established before his death by a duly transcribed or published deed, provided that the notarised certificates mentioned in 3° of article 28 of decree n° 55-22 of 4 January 1955 reforming land registration, relating to such property, are published within the same timeframe.