Language diversity and language contact : essays / by Stanley Lieberson ; selected and introduced by Anwar S. Dil. Lieberson, Stanley, 1933- Dil, Anwar S. Sociolinguistics. Areal linguistics. 420 LIL Includes bibliographical references. Stanford, Calif. : Stanford University Press, 1981. 1981. 1981 Text xiv, 390 p. : eng Language science and national development