In 1990s based on the eigenfunction method of representation theory of groups, a new method, the symmetrized boson representation (SBR) method, was brought forward.

90年代，陈金全等人在点群的表示理论上提出了一种新的方法，对称化玻色表象方法(SBR)。

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In theory, groups of countries could pool reserves, so that a smaller amount would suffice than if countries each maintain their own buffers.

ECONOMIST: Reserve currencies

Advocates of this theory argue that both groups were the original inhabitants of Europe before migratory waves of Indo-Europeans came from the east.

BBC: The hard work begins

That's the theory of the poet who takes groups of men into the woods to bang drums and helps us get in touch with our proud, warlike selves.

NPR: Excerpt: 'The Practice of Deceit'