TY  - BOOK
AU  - Twyman, Frank
TI  - PRISM AND LENS MAKING
U1  - 681.41 
PY  - 1952///
CY  - London
PB  - Hilger & Watts
KW  - Prisms
KW  - Lenses
KW  - Hilger (Adam) Ltd., London
ER  -