1975 January, Andrejs Plakans, "Peasant Farmsteads and Households in the Baltic Littoral, 1797", in Raymond Grew et al (eds.), Comparative Studies in Society and History: An International Quarterly, Cambridge University Press, volume 17, number 1, page 19, The work force norm imposed on adults the need to join in a common effort aimed at survival, which was a condition qualitatively different from a group of coresident individuals having similar or identical occupations happenstantially.
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