TY  - BOOK
AU  - CLAY (Reginald S)
TI  - Treatise on practical light
U1  - 534/27 
PY  - 1911///
CY  - London
PB  - Macmillan & Co. Ltd.
KW  - Treatise
KW  - practical
KW  - on
KW  - light
ER  -