The Saint and the Hapsburg Necklace

Blurb

The Saint and the Hapsburg Necklace is the title of a 1976 mystery novel featuring the character of Simon Templar, alias "The Saint". The novel is written by Christopher Short, but per the custom at this time, the author credit on the cover goes to Leslie Charteris, who created the Saint in 1928, and who served in an editorial capacity.
The book was first published in the United States by The Crime Club, and was followed thereafter by a United Kingdom edition from Hodder and Stoughton. A later paperback edition by Coronet Books was a tie-in with the then-current Return of the Saint television series.
Although the proper spelling of the name should be Habsburg, all editions of this book use the "Hapsburg" spelling.