TY - ECHAP AU - N. Weiss AU - S. Tobias DO - 10.1007/BFb0105669 M1 - Lecture Notes in Physics PB - Springer Berlin Heidelberg PY - 1997 SN - 978-3-540-63072-2 SP - 25 EP - 47 TI - Modulation of solar and stellar activity cycles VL - 489 ER -