@inbook{8757,
  author = {S. Saar},
  title = {The photospheric magnetic fields of cool stars: Recent results of survey and time-variability programs},
  year = {1987},
  volume = {291},
  number = {Lecture Notes in Physics},
  pages = {10-20},
  publisher = {Springer Berlin Heidelberg},
  address = {Berlin, Heidelberg},
  isbn = {978-3-540-18653-3},
  doi = {10.1007/3-540-18653-0_99},
}