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2. Y. L. Song, M. Zhang, On the relationship between sunspot structure and magnetic field changes associated with solar flares, 2016, ApJ, 826, 173;

3. J. Hao, M. Zhang, Hemispheric helicity trend for solar cycle 24, 2011, ApJ Letters, 733, L27;

4. C. Y. Wang, M. Zhang, A hemispheric helicity sign rule indicated by large-scale photospheric magnetic fields at three phases of solar cycle 23, 2010, ApJ, 720, 632-638;

5. D. Wang, M. Zhang, H. Li & H. Q. Zhang, A cross-comparison of cotemporal magnetograms obtained with MDI/SOHO and SP/Hinode, 2009, Solar Physics, 260, 233-244;

6. M. Zhang, N. Flyer, The dependence of the helicity bound of force-free magnetic fields on the boundary conditions, 2008, ApJ, 683, 1160-1167;

7. M. Zhang, Helicity observation of weak and strong fields, 2006, ApJ, 646, L85-L88;

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9. M. Zhang, B. C. Low, The hydromagnetic nature of solar coronal mass ejections, 2005, Annual Reviews of Astronomy and Astrophysics, 43, 103-137;

10. M. Zhang, B. C. Low, Magnetic-flux emergence into the solar corona. III. The role of total helicity conservation, 2003, ApJ, 584, 479-496.