On friday last week I started a vendiagram about Tupaia the navigator and Iris and the dogstar. A vendiagram is when you draw two cirles next to eachother to make a gap in the middle, once you done that you write the names of the people/books your doing the vendiagram ontop of each circle, In the gap you write their similaritys and in the two circles you write their diffrences. Here is mine. 
Have you read either of these stories? Let me know in the comments.