@Article{angeo-28-917-2010,
AUTHOR = {Nevanlinna, H. and H\"akkinen, L.},
TITLE = {Results of Russian geomagnetic observatories in the 19th century:  magnetic activity, 1841–1862},
JOURNAL = {Annales Geophysicae},
VOLUME = {28},
YEAR = {2010},
NUMBER = {4},
PAGES = {917--926},
URL = {https://angeo.copernicus.org/articles/28/917/2010/},
DOI = {10.5194/angeo-28-917-2010}
}