Rubin, Joan. 1968. Bilingual Usage In Paraguay. In Fishman, Joshua A. (ed.), Readings in the Sociology of Language, 512-530. Berlin, Boston: De Gruyter.
http://www.degruyter.com/view/books/9783110805376/9783110805376.512/9783110805376.512.xml
@incollection{121561, address = {Berlin, Boston}, author = {Rubin, Joan}, booktitle = {Readings in the Sociology of Language}, editor = {Fishman, Joshua A.}, pages = {512-530}, publisher = {De Gruyter}, title = {Bilingual Usage In Paraguay}, url = {http://www.degruyter.com/view/books/9783110805376/9783110805376.512/9783110805376.512.xml}, year = {1968} }