Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: On ${\bf W_{\infty}}$ Algebras, Gauge Equivalence of KP Hierarchies,
  Two-Boson Realizations and their KdV Reductions
15
The categories of this paper are: nucl-ex
11
The categories of this paper are: hep-lat
0
The categories of this paper are: hep-ph
34
The categories of this paper are: chem-ph
31
The categories of this paper are: ao-sci
16
The categories of this paper are: stat
27
The categories of this paper are: comp-gas
22
The categories of this paper are: chao-dyn
35
The categories of this paper are: mtrl-th
36
The categories of this paper are: cmp-lg
37
The categories of this paper are: supr-con
12
The categories of this paper are: nucl-th
14
The categories of this paper are: math-ph
24
The categories of this paper are: dg-ga
19
The categories of this paper are: eess
29
The categories of this paper are: funct-an