TY  - BOOK
AU  - Feynman,Richard P.
AU  - Penrose,Roger
TI  - Six not- so - easy pieces : : Einstein's relativity, symmetry, and space-time
SN  - 0201150255
U1  - 530.11 
PY  - 1997///
CY  - New York
PB  - Addison-Wesley, 
KW  - Physics
KW  - Symmetry
KW  - Relativity
KW  - Time
ER  -