TY  - BOOK
AU  - Richter, Nikolaus B
AU  - 
TI  - Nature of comets
U1  - 523.6 
PY  - 1965///
CY  - London
PB  - Methiuen
KW  - Astronomical physics
KW  - Physics, Astronomical
KW  - Astrophysics
KW  - Spectroscopy
KW  - black holes
KW  - Spectrum analysis
KW  - Astronomy
KW  - Physics
KW  - Stars
KW  - Comets
ER  -