TransliterationRykachev M. A. Otchet po Nikolaevskoy Glavnoy Fizicheskoy Observatorii za 1909 g., predstavlennyy Imperatorskoy Akademii Nauk Direktorom Observatorii M. Rykachevym. (Dolozheno v zasedanii Fiziko-Matematicheskogo Otdeleniya 29 aprelya 1910 g.).
In EnglishRykachev M. A. Report on the Nikolaev Main Physical Observatory for 1909, submitted to the Imperial Academy of Sciences by the Director of the Observatory, M. Rykachev (reported in the meeting of the Physics and Mathematics Department on April 29, 1910). In Russian
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