Show your Booklets here

The original owner probably got the booklet in an official post office agency mailing. Some of the European postal agencies would put cancelled stamps in the mailing along with the other stamps, instead of putting them on the envelope/package. That would keep the stamps from being damaged -- but of course they would still be gummed. They look like CTOs/remaindered, but they should be considered to be postally used favor canceled. I've seen similar examples that were part of a stamp mailing from the Austrian post office. I liked the Austrian cancelled stamps because they used a dated circular cancel instead of the generic round/oval (mute) cancel.