TY  - BOOK
AU  - Langan, John
AU  - Johnson, Beth 
TI  - English essential 
SN  - 978-0-07-131788-7
U1  - 425 23rd ed. 
PY  - 2013///
CY  - New York : 
PB  - McGraw Hill; 
KW  - English language- Grammar
UR  - www.mhhe.com
ER  -