[1]Claeson T, H¨ormander L. Integrationsteori. Studentlitteratur. 1970
[2]Campanato S. Equazioni ellittiche del second ordine e spazi L2,. Ann Mat Pura e apll, 1965,69: 321-380
[3]Giaguinta M. Multiple Integrals in the Culculus of Variations and Non-linear Elliptic Systems. Princ Univ Press, 1983
[4]Jerison D. The Poincar´e inequality for vector fields satisfying H¨ormander’s conditions. Duke Math J,1986,53: 503-523
[5]Nagel A, Stein E M, Wainger. Balls and metrics defined by vector fields I, basic properties. Acta Math,1985,155: 103-147
[6]Prato da G. Spazi Lp,(
, ) e loro propriet`a. Ann Mat Pura e Appl, 1965, 69: 384-392
[7]Qi M Y, Zhang G P. Asymptotic expansion of Dirac-type distribution associated with a class of hypersurfaces with degenerated critical points. Acta Math Scientia, 1999, 19(2): 127-137
[8]Xu C J, Zuily C. Higher interior regularity for quasilinear subelliptic systems. Calcul Var PDE, 1997, 5:323-343
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