Trend of photospheric magnetic helicity flux in active regions generating halo coronal mass ejectionsA. Smyrli, F. Zuccarello, P. Romano, F. P. Zuccarello, S. L. Guglielmino, D. Spadaro, A. W. Hood and D. MackayA&A, 521 (2010) A56DOI: https://doi.org/10.1051/0004-6361/200913275
