Observational exobiology.
Proceedings article published in 1989 by
M. J. S. Belton,
A. L. Betz,
J. H. Black,
M. Cohen,
T. Encrenaz,
N. Evans 
,
P. D. Feldman,
E. Herbst,
J. Kerridge,
C. McKay,
J. Nuth,
T. Roellig,
T. Scattergood,
J. Tarter,
A. Tielens
and other authors.
,
P. D. Feldman,
E. Herbst,
J. Kerridge,
C. McKay,
J. Nuth,
T. Roellig,
T. Scattergood,
J. Tarter,
A. Tielens
and other authors.
