TY  - BOOK
AU  - JOHNSON.B.K
TI  - Optics and Optical Instruments :  An Introduction
SN  - 9780486606422
U1  - 681.4 
PY  - 1960///
CY  - New York
PB  - DOVER
N1  - REFLECTION AND REFRACTION--FOCAL LENGTH MEASUREMENTS--eye--telescope--microscope--photographic lens--optical glass
ER  -