3Qiu E J, Xu Q. A simple adjoint method of wind analysis for single--Doppler data [J]. Journal of Atmospheric and Oceanic Technology, 1992, 9: 588-598.
4Xu Q, Qiu C J. Simple Adjoint Methods for Single-Doppler Wind Analysis with Strong Constraint of Mass Conservation [J]. Journal of Atmospheric and Oceanic Technology, 1994 11:289-298.
5Xu Q, Qiu C J. Adjoint-Method Retrievals of Low-Altitude Wind Fields from Single-Doppler Reflectivity and Radial-Wind Data [J]. Journal of Atmospheric and Oceanic Technology, 1995, 12:1111-1119.
6Xu Q, et al. Simple Adjoint Retrievals of Microburst Winds from Single-Doppler Radar Data [J]. Mort Weather Rev, 1995, 123: 1822-1833.
7Xu Qin, Gu Hongdao, Yang Shuowen. Simple Adjoint Methods for Three-Dimensional Wind Retrievals from Single-Doppler Radar [J]. Q J R Meteor Soc, 2001(127): 1053-1067.