Chen, J., Howard, R. A., Brueckner, G. E., Santoro, R., Krall, J., Paswaters, S. E., St.Cyr, O. C., Schwenn, R., Lamy, P., & Simnett, G. M. (1997). Evidence of an erupting magnetic flux rope: LASCO coronal mass ejection of 1997 April 13. Astrophysical Journal, 490, L191-L194.