Multiline Zeeman signatures through line additionM. Semel, J. C. Ramírez Vélez, M. J. Martínez González, A. Asensio Ramos, M. J. Stift, A. López Ariste and F. LeoneA&A, 504 3 (2009) 1003-1009DOI: https://doi.org/10.1051/0004-6361/200810428