Visitors are flocking to see the characters in an unusual menage a trois at San Francisco zoo.

游客们正聚集起来，观看旧金山动物园里一场不寻常的三角恋中的角色。

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Previous studies of Trois Hommes Armes de Lances had used X-ray fluorescence - which yields a list of all the atoms within an object - but showed that there were atoms present in the work that were not present on the surface.

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