| title | ISBN-13 (ISBN-10) | year of publication |
|---|---|---|
| 1983 Outlook for Travel and Tourism Proceedings of the 1983 Travel Outlook Forum | 978-99938-1-997-4 (99938-1-997-2) | 1983 |
| Outlook for Travel and Tourism: Proceedings, 1985/86 | 978-99971-2-426-5 (99971-2-426-X) | 1985 |