TY  - BOOK
AU  - Welford,W.T.
TI  - Aberrations of the symmetrical optical system
SN  - 0127420509
AV  - QC372.2.D4 W44
U1  - 535/.2 
PY  - 1974///
CY  - London
PB  - Academic Press
KW  - Optical instruments
KW  - Design and construction
KW  - Aberration
KW  - Geometrical optics
N1  - Includes bibliographical references and indexes
ER  -