TY  - BOOK
AU  - Porter,M.W.
AU  - Spiller,R.C.
TI  - The Barker index of crystals : a method for the identification of crystalline substances
U1  - 548 POR S.2-2  
PY  - 1956///.
CY  - Cambridge : 
PB  - W. Heffer & Sons, Ltd., 
KW  - Crystallography
ER  -