Long- and short-term variability in O-star winds. I. Time series of UV spectra for 10 bright O starsL. Kaper, H. F. Henrichs, J. S. Nichols, L. C. Snoek, H. Volten and G. A.A. ZwarthoedAstron. Astrophys. Suppl. Ser., 116 2 (1996) 257-287DOI: https://doi.org/10.1051/aas:1996113