TY  - BOOK
AU  - Sankoff,David
TI  - Linguistic variation: models and methods 
SN  - 0126188505
AV  - P120.V37 L52
U1  - 410 SAN 
PY  - 1978///
CY  - New York
PB  - Academic Press
KW  - Language and languages
KW  - Variation
N1  - Includes bibliographies and indexes
ER  -