[1]   郑神州, 方爱农. 双特征的Beltrami方程和拟正则映射. 数学学报, 1997, 40(5): 745--750

[2]  程金发, 方爱农. 偶数维空间上广义Beltrami方程组及高维空间的Beltrami方程组. 数学年刊, 1997, 18A(6):
789--798

[3]  程金发, 方爱农. $(G,H)$ -拟正则映照和$B$ -调和方程. 数学学报, 1999, 42(5): 883--888

[4]  高红亚,吴泽民. 关于双特征Beltrami方程组. 数学物理学报, 2002, 22(4): 433--440

[5]  Reshetnyak Yu G. Space Mappings with Bounded Distortion. Trans Math Monographs. Providence, RI: Amer Math Soc, 1989

[6]  Rickman S. Quasiregular Mappings. Berlin, Heidelberg: Spriner-Verlag, 1993

[7]  Iwaniec T, Martin G.Geometric Function Theory and Non-linear Analysis. Oxford: Clarendon Press, 2001

[8]  Iwaniec T, Martin G. Quasiregular mappings in even dimensions.  Acta Math, 1993, 170: 29--81

[9]  Iwaniec T. p-harmonic tensors and quasiregular mappings. Ann of Math, 1992, 136: 589--624

[10]  Vekua I N. Generalized Analytic Functions. Oxford: Peramon Pres, 1962

[11]  Bers L. Theory of Pseudo-analytic Functions. Lecture Note (Mimeographed). New York:  New York University, 1953

[12]  闻国椿. 线性与非线性椭圆型复方程. 上海:上海科学技术出版社, 1986

[13]  Manfredi J J. Weakly monotone functions. J Geom Anal, 1994, 4: 393--402

[14]  Koskela P, Manfredi J J, Vilamor E. Regularity theory and traces of $\cal A$-harmonic functions. Trans Amer Math Soc, 1996, 348: 755--766

[15]  高红亚. 弱拟正则映射的若干性质. 数学学报, 2002, 45(1): 191--196