I cannot find the following 4 papers by Sekiguchi–Suwa in their works on Kummer–Artin–Schreier–Witt theory:

1. On the unified Kummer–Artin–Schreier–Witt theory, Prépublications du laboratoire de Mathématiques Pures de Bordeaux, Prépublication nº 111 (1999).
2. On the unified Kummer–Artin–Schreier–Witt sequences
3. Théories de Kummer–Artin–Schreier–Witt, C. R. Acad. Sci. Paris 319 (1994), 105-110.
4. Theorie de Kummer–Artin–Schreier, C. R. Acad. Sci. Paris 312 (1991), 417-420.

I will be very happy if someone can help me.

Thanks.