For the first time in the 1980's a series of James Bond paperbacks was published that not only featured the original 14 Ian Fleming titles but also many titles by continuation authors. This fine series was published by Coronet, and there were two titles in particular that stand out to me for their variant covers.
The first is "Dr No. Almost all printings of this title feature a spider on a black background. That is, except for the now well known 9th edition which features a woman's hand (Honey Rider's ?) holding a knife on a blue background. A full explanation for this anomaly can be found on The Book Bond website.
However there are also other subtle variation covers for this Coronet title. They all relate to the author's name at the base of the cover. The standard text is grey embossed, but there's also white embossed and grey flat (the latter two being 14th printings). I have found no explanation for these changes which appear to be more than just printing errors. Regardless, the four covers all have the same barcode: 9780340418994 00599 and ISBN: 0340418990.
I'm really curious about these cover variations and why they exist. I wonder if there are more subtle differences for this Coronet series out there ? And I'm also puzzled if Coronet was prepared to play with cover text styles why they didn't fix a glaring mistake with this series in subsequent printings, the omission of the image from the spine of "Live And Let Die", the only cover as such ?