TY  - BOOK
AU  - Portree, David S. F.
CN  - NAS 1.21:
CN  - TL799.M3
CY  - Washington, DC :
DA  - 2001.
ID  - 289216
KW  - Space flight to Mars
N1  - "February 2001."
N1  - Shipping list no.: 2003-0099-M.
N1  - "NASA Center for AeroSpace Information (CASI), Global connection to aerospace research"--Cover.
PB  - NASA History Division, Office of Policy and Plans, NASA Headquarters,
PP  - Washington, DC :
PY  - 2001.
T1  - Humans to Marsfifty years of mission planning, 1950-2000 /
TI  - Humans to Marsfifty years of mission planning, 1950-2000 /
VL  - no. 21
VL  - 2001-4521
ER  -