1978 Space: 1999 convention book, signed by the series creator, Gerry Anderson and cast members Martin Landau, Dave Prowse, Nick Tate, and Clifton Jones. The signatures are all on the inside front page of the convention book and they are inscribed to "Ken".
Also included with this item are two copies of the convention program, an pre-con information sheet, and Update: Four with information about the convention. Please see photos.
The convention was held July 28 - 30, 1978 in Columbus, Ohio. It was put on by the National Save: 1999 Alliance. I found a report online that said there were about 500 people in attendance.
I do not have any certification for the signatures. I acquired these items as part of a box lot of TV fan magazines. I didn't realize until I got them home that they were signed. There were also some press materials for the show in the lot and I have those currently listed in a separate auction that started last week.