|
1. |
|
per National Geographic Society (É.-U.); |
Sito web : Document : Updating website Risorsa costantemente aggiornata Computer file |
French |
1996
|
Washington, D.C. : National Geographic Society
|
Biblioteche WorldCat |
|
2. |
|
per National Geographic Society (États-Unis); |
Rivista, giornale : CD for computer : Document Computer file |
Inglese |
1996
|
Washington, D.C. : National Geographic Society
|
Biblioteche WorldCat |