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The Palais des Papes in Avignon is the best complete large royal palace, alongside the Royal palace of Olite, built during the 13th and 14th centuries for the kings of Navarre. The Malbork Castle built for the master of the Teutonic order is an example of Brick Gothic architecture. Partial survivals of former royal residences include the Doge's Palace of Venice, the Palau de la Generalitat in Barcelona, built in the 15th century for the kings of Aragon, or the famous Conciergerie, former palace of the kings of France, in Paris.

When was the Palau de la Generalitat in Barcelona constructed?
Answer: built in the 15th century
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With continuing European integration, the European Union is increasingly being seen as a great power in its own right, with representation at the WTO and at G8 and G-20 summits. This is most notable in areas where the European Union has exclusive competence (i.e. economic affairs). It also reflects a non-traditional conception of Europe's world role as a global "civilian power", exercising collective influence in the functional spheres of trade and diplomacy, as an alternative to military dominance. The European Union is a supranational union and not a sovereign state, and has limited scope in the areas of foreign affairs and defence policy. These remain largely with the member states of the European Union, which include the three great powers of France, Germany and the United Kingdom (referred to as the "EU three").

What other tools are used as alternative to military force?
Answer: trade and diplomacy
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Contemporary Eastern Orthodox Christians often object to the dogmatic declaration of her immaculate conception as an "over-elaboration" of the faith and because they see it as too closely connected with a particular interpretation of the doctrine of ancestral sin. All the same, the historical and authentic tradition of Mariology in Byzantium took its historical point of departure from Sophronios, Damascene, and their imitators. The most famous Eastern Orthodox theologian to imply Mary's Immaculate Conception was St. Gregory Palamas. Though many passages from his works were long known to extol and attribute to Mary a Christlike holiness in her human nature, traditional objections to Palamas' disposition toward the Immaculate Conception typically rely on a poor understanding of his doctrine of "the purification of Mary" at the Annunciation. Not only did he explicitly cite St. Gregory Nazianzen for his understanding of Jesus' purification at His baptism and Mary's at the Annunciation, but Theophanes of Nicaea, Joseph Bryennius, and Gennadios Scholarios all explicitly placed Mary's Conception as the first moment of her all-immaculate participation in the divine energies to such a degree that she was always completely without spot and graced. In addition to Emperor Manuel II and Gennadius Scholarius, St. Mark of Ephesus also fervently defended Mary's title as "prepurified" against the Dominican, Manuel Calecas, who was perhaps promoting thomistic Mariology that denied Mary's all-holiness from the first moment of her existence.

What in particular does the group feels is impossible to believe ?
Answer:
because they see it as too closely connected with a particular interpretation of the doctrine of ancestral sin.