Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The trace problem for vector fields satisfying H\"ormander's condition   Trace theorems are proved for non-isotropic Sobolev and $L^p$-Lipschitz
spaces defined by vector fields satisfying H\"ormander's bracket condition of
order 2. It is shown that the loss of regularity by traces is the same as in
the classical case.

29
The categories of this paper are: funct-an
13
The categories of this paper are: quant-ph
4
The categories of this paper are: cond-mat
5
The categories of this paper are: gr-qc
28
The categories of this paper are: alg-geom
33
The categories of this paper are: plasm-ph
12
The categories of this paper are: nucl-th
27
The categories of this paper are: comp-gas
21
The categories of this paper are: adap-org
15
The categories of this paper are: nucl-ex
24
The categories of this paper are: dg-ga
34
The categories of this paper are: chem-ph
9
The categories of this paper are: nlin
23
The categories of this paper are: solv-int
11
The categories of this paper are: hep-lat
25
The categories of this paper are: patt-sol