Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Gravitational Instantons of Type D_k   We use two different methods to obtain Asymptotically Locally Flat
hyperkahler metrics of type D_k.

15
The categories of this paper are: nucl-ex
1
The categories of this paper are: cs
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The categories of this paper are: hep-ex
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The categories of this paper are: econ
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The categories of this paper are: hep-lat
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The categories of this paper are: eess
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The categories of this paper are: quant-ph
9
The categories of this paper are: nlin
36
The categories of this paper are: cmp-lg
32
The categories of this paper are: atom-ph
5
The categories of this paper are: gr-qc
31
The categories of this paper are: ao-sci
23
The categories of this paper are: solv-int
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The categories of this paper are: q-alg
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The categories of this paper are: funct-an
37
The categories of this paper are: supr-con