Reference Correction
In the original publication [1], there was an error in reference [20]. The article “Han, J. Auto-disturbances-rejection Controller and Its Applications. Control Decis. 1998, 13, 19–23.” was not the intended reference for the tracking differentiator and was incorrectly recorded in the reference list. The correct reference [20] should be the following:
Han, J.Q.; Wang, W. Nonlinear tracking-differentiator. J. Syst. Sci. Math. Sci. 1994, 14, 177–183. (In Chinese)
Accordingly, reference [20] has been updated in the reference list. The authors state that the scientific conclusions are unaffected. This correction was approved by the Academic Editor. The original publication has also been updated.
Reference
- Shi, Z.; Zhang, C.; Zhang, G. Active Disturbance Rejection-Based Tracking Control of Robotic Manipulators Under a Universal Symmetry Constraint Framework. Symmetry 2026, 18, 919. [Google Scholar] [CrossRef] [Scilit]
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