hj, anh Picvendor down giúp em mấy bài này với ạ

1. Optimal adaptive control for estimation of parameters of ARX models
http://www.ieeexplore.ieee.org/searc...d%3DSearch+All
2. Least squares parameter estimation of continuous-time ARX models from discrete-time data
http://www.ieeexplore.ieee.org/searc...d%3DSearch+All
3.Mixed linear system estimation and identification
http://www.ieeexplore.ieee.org/searc...d%3DSearch+All
4.An improved error estimate for reduced-order models of discrete-time systems
http://www.ieeexplore.ieee.org/searc...d%3DSearch+All