TY  - BOOK
ED  - Indian standards institution                                                                                                                                                                                                                                   . 
TI  - Code of practice for determination of specific surface area of powders by air permeability methods,IS:8425-1977 / 
U1  - 620.168 
PY  - 1977///
CY  - New Delhi : 
PB  - Indian standards institution , 
ER  -