TY  - BOOK
AU  - Petters, A O.
AU  - Levine, H.
AU  - Wambsganss, J.
TI  - Singularity Theory and Gravitational Lensing : (PMP 21)
SN  - 0 8176 3668 4
CY  - Boston
KW  - Gravitational Lenses - Mathematics
KW  - Singularities (Mathematics)
ER  -