The book Nomads of Gor has two people riding a bird on the cover.
A naked man and woman ride a giant hawk on the cover of a book called Nomads Of Gor
An old book by John Norman called Nomads of Gor.
The cover of the book Normads of Gor features a man and woman riding a giant bird.
A book with a couple riding an eagle titled Nomads of Gor.