| [1] | S. Li, Z. S. Gao. A note on the Bruck conjecture. Archiv Der Mathematik, 2010, 95(3): 257-268. | 
                     
                                
                                    
                                        | [2] | W. Hayman. Meromorphic function. Oxford: Clarendon Press, 1964. | 
                     
                                
                                    
                                        | [3] | I. Laine. Nevanlinna theory and complex differential equation. Berlin: Walter de Gruyter, 1993. | 
                     
                                
                                    
                                        | [4] | 杨乐. 值分布论及其新研究[M]. 北京: 科学出版社, 1982. | 
                     
                                
                                    
                                        | [5] | 仪洪勋, 杨重骏. 亚纯函数唯一性理论[M]. 北京: 科学出版社, 1995. | 
                     
                                
                                    
                                        | [6] | L. A. Rubel, C. C. Yang. Values shared by an entire function and its derivative. Complex Analysis, Lecture Notes in Math, 1977, 599: 101-103. | 
                     
                                
                                    
                                        | [7] | Y.-M. Chiang, S.-J. Feng. On the Nevanlinna characteristic of   and difference equations in the complex plane. The Ramanujan Journal, 2008, 16(1): 105-129. | 
                     
                                
                                    
                                        | [8] | Y.-M. Chiang, S.-J. Feng. On the growth of logarithmic differences, difference quotients and logarithmic derivatives of meromorphic functions. Transaction of American Mathematical Society, 2009, 361(7): 3767-3791. | 
                     
                                
                                    
                                        | [9] | R. G. Halburd, R. J. Korhonen. Nevanlinna theory for the difference operator. Annals Academy Scientiarum Fennicy Mathematical, 2006; 31(2): 463-478. | 
                     
                                
                                    
                                        | [10] | R. G. Halburd, R. J. Korhonen. Difference analogue of the lemma on the logarithmic derivative with applications to difference equations. Journal of Mathematical Analysis and Applications, 2006, 314(2): 477-487. | 
                     
                                
                                    
                                        | [11] | J. Heittokangas, R. Korhonen, I. Laine, J. Rieppo and J. L. Zhang. Value sharing results for shifts of meromorphic functions, and sufficient conditions for periodicity. Journal of Mathematical Analysis and Applications, 2009, 355(1): 352-363. | 
                     
                                
                                    
                                        | [12] | W. Bergweiler, J. K. Langley. Zeros of differences of meromorphic functions. Mathematical Proceedings of the Cambridge Philosophical Society, 2007, 142: 133-147. | 
                     
                                
                                    
                                        | [13] | J. Wang. Growth and poles of meromorphic solutions of some difference equations. Journal of Mathematical Analysis and Applications, 2011, 379: 367- 377. |