TY  - RPRT
TI  - The relationship of active comets, 'extinct' comets, and dark asteroids
AU  - Hartmann, William K.
AU  - Tholen, David J.
AU  - Cruikshank, Dale P.
PY  - 1987
UR  - https://ntrs.nasa.gov/citations/19870044305
ID  - 19870044305
ER  -