TransliterationRykachev M. A. Otchet po Nikolaevskoy Glavnoy Fizicheskoy Observatorii za 1906 g., predstavlennyy Imperatorskoy Akademii Nauk Direktorom Observatorii M. Rykachevym. (Dolozheno v zasedanii Fiziko-Matematicheskogo Otdeleniya 16 maya 1907 g.).
In EnglishRykachev M. A. Report on the Nikolaev Main Physical Observatory for 1906, 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 May 16, 1907). In Russian
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