The Virtual Secretary Architecture for Secure Software Agents. - Gunnar Hartvigsen; Svein-Gunnar Johansen; A. Helme; Roy Arild Widding; Johan Gustav Bellika; Wen Cao (PAAM, 1996)

Using User Models in Software Agents: The Virtual Secretary. - Johan Gustav Bellika; Gunnar Hartvigsen; Roy Arild Widding (ICMAS, 1998)

The Virtual Library Secretary - A User Model Based Software Agent. - Johan Gustav Bellika; Gunnar Hartvigsen; Roy Arild Widding (Pers. Ubiquitous Comput., 1998)