TY - ECHAP AU - C. Schrijver AU - J. Cote CY - Berlin, Heidelberg DO - 10.1007/3-540-18653-0_106 M1 - Lecture Notes in Physics PB - Springer Berlin Heidelberg PP - Berlin, Heidelberg PY - 1987 SN - 978-3-540-18653-3 SP - 51 EP - 53 TI - The relation between the CA II K line-core flux density and the magnetic flux density on the sun VL - 291 ER -