Below is an example.
Aesop, the King of Fables, wrote a fable about "Avaricious and Envious."
Victor Hugo wrote a poem called "Envy and Avarice," based on the fable.
I wrote a short story, "Prince Jack," based loosely on Hugo's poem.
Both translations of Aesop's fable, and Hugo's poem are in the public domain. Prince Jack is copyright 2000, John Newmark, All Rights Reserved