| nsf.gov | National Science Foundation |
| archive.org | Internet Archive |
| psu.edu | CiteSeer: The NEC Research Institute Scientific Literature Digital Library |
| ncstrl.org | NCSTRL - Networked Computer Science Technical Reference Library |
| nationalacademies.org | National-academies.org | Publications |
| ecu.edu | North Carolina History and Fiction Digital Library |
| cdc.gov | US - - Centers for Disease Control and Prevention (CDC) |
| loc.gov | THOMAS |
| promo.net | Project Gutenberg Official Home Site - Index -- Free Books On-line |
| fcla.edu | Everglades Digital Library |
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