| [1] Anna Z. Very weak solutions of nonlinear subelliptic equations. Annales Academiae Scientiarum Fennicae Mathematica, 2005, 30: 407--436
[2] Garofalo N, Nhieu D M. Isoperimetric and Sobolev inequalities for Carnot-Carathéodory spaces and the
existence of minmal surfaces. Comm Pure Appl Math, 1996, 49: 1081--1144
[3] Gutiérrez C E, Lanconelli E. Maximum principle, non-homogeneous Harnack inequality, and Liouville theorems for X-elliptic operations. Comm Part Diff Eqs, 2003, 28(11/12): 1833--1862
[4] Iwaniec T. p-harmonic tensor and quasiregular mappings. Ann Math, 1992, 136(3): 589--624
[5] Iwaniec T, Sbordone C. Weak minima of variational integrals. J Reine Angew Math, 1994, 454(1): 143--161
[6] Iwaniec T, Lutoborski A. Integral estimates for null Lagrangians. Arch Rat Mech Anal, 1993, 125: 25--29
[7] Iwaniec T, Migliaccio L, Nania L, Sbordone C. Integrability and removability results for quasiregular mappings in high dimensions. Math Scand, 1994, 75(2): 263--279
[8] Lewis J. On very weak solution of certain elliptic systems. Comm Part Diff Equ, 1993, 18(9/10): 1515--1537
[9] Carozza M, Antonia P Di N. On very weak solutions of a class of nonlinear elliptic systems. Comment Math Univ Carolinae, 2000, 41(3): 493--508
[10] Zheng S Z, Fang A N. Regularity of very weak solutions for a class of nonlinear elliptic systems. Acta Mathematica Sinica, 1998, 14: 733--740
[11] Zheng S Z. The Lp-integrability of Beltrami's equations with non-natural exponents. Acta Mathematica Scientia, 1998, 18: 13--20
[12] Zheng S Z. Regualrity results for the generalized Beltrami system. Acta Math Sin, 2004, 20(2): 193--204
[13] Zheng S Z. Removable singularities of solutions of A-harmonic type equation. Acta Math Appl Sin, 2004, 20(1): 115--122
[14] Hömander L. Hypoellptic second order differential equations. Acta Math, 1967, 119: 147--171
[15] Rothschild L P, Stein E M. Hypoelliptic differential operators and nilpotent groups. Acta Math, 1976, 138: 247--320
[16] Folland G B. Subelliptic estimates and function spaces on nilpotent Lie groups. Ark Mat, 1975, 13(2): 161--207
[17] Stein E M. Singular Integrals and Differentiability Properties of Functions. Princeton: Princeton Univ Press, 1970
[18] Di Fazio G, Zamboni P. Hölder continuity for quasilinear subelliptic equations in Carnot Carathéodory spaces.
Math Nachr, 2004, 272: 3--10 |