Não informado. (1939). Quarterly Bulletin on Solar Activity. International Astronomical Union.
Style de citation Chicago (17e éd.)Não informado. Quarterly Bulletin on Solar Activity. Zurich, Suíça: International Astronomical Union, 1939.
Style de citation MLA (8e éd.)Não informado. Quarterly Bulletin on Solar Activity. International Astronomical Union, 1939.
Attention : ces citations peuvent ne pas être correctes à 100%.