Language and society : Essays presented to Arthur M. Jensen on his seventieth birthday (1961) was published in Copenhagen, indicating that he was born in 1891. Apparently the author of English by the nature method (1939; an edition from 1942 was digitized by the Internet Archive), and founder of "Naturmetodens Sproginstitut". There is a brief biography in Dagens Nyheter 21 November 1959, stating he was born in Aalborg in 1891.
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others born in 1891
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