TY  - BOOK
AU  - Lewis,Richard S.
TI  - Space in the 21st century
SN  - 0231063040 (alk. paper)
AV  - TL790.L395 1990 
PY  - 1990///
CY  - New York
PB  - Columbia University Press
KW  - Space colonies
KW  - Outer space
KW  - Exploration
ER  -