Hachinger, S.; Röpke, F. K.; Mazzali, P. A.; Gal-Yam, A.; Maguire, K.; Sullivan, M.; Taubenberger, S.; Ashall, C.; Campbell, H.; Elias-Rosa, N.; Feindt, U.; Greggio, L.; Inserra, C.; Miluzio, M.; Smartt, S. J.; Young, D.: Type Ia supernovae with and without blueshifted narrow Na?i D lines ? how different is their structure? 2017Monthly Notices of the Royal Astronomical Society: 471. https://doi.org/10.1093/mnras/stx1578