They thought it w...

 The Rosebud Annual

 De Avonturen van ...

 Happy Moments wit...

 Jack-In-The-Box

 Plainly Philip Is...

 The Vanquished

 S Is a Scholar - ...

 Tibby and Tabby

 A Night Out

 I Don't Think!

 A Line of Sulphurers

 Academy of Cats

 Frolics in Catlan...