High Order Solutions and Generalized Darboux Transformations of   Derivative Schr\"odinger Equation
  By means of certain limit technique, two kinds of generalized Darboux transformations are constructed for the derivative nonlinear Sch\"odinger equation (DNLS). These transformations are shown to lead to two solution formulas for DNLS in terms of determinants. As applications, several different types of high order solutions are calculated for this equation. 
Boling Guo, Liming Ling and Q. P. Liu
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