Sergey V. Petrov (1911–1988), a famous Russian writer and translator, suggested his etymology of the word “ать” during the Second Nordic conference in Leningrad in 1965. He explained that the word was based on the Swedish ett, (två, tre) which Swedish military instructors introduced to Russian solders in the 17th century. At the same conference the author of the article suggested his etymology, based on the Phonetic changes of the Russian
«раз-два…». The article shows the stages of transformation.
BORIS ZHAROV. S. V. PETROV & DISCUSSION ABOUT SWEDISH ETYMOLOGY OF “АТЬ-ДВА”