An Abundance of Katherines is written by John GreenJohn Green wrote The Fault in Our StarsThe Fault in Our Stars is written by John Green. John Green : `Sibling`: Hank Green
[Human]:  My friend just read An Abundance of Katherines and loved it. Can you recommend it for me too?  [Assistant]: Sure, it's by John Green and is Young adult fiction. Do you like that genre? [Human]: Not so much, but John Green is actually not bad. What else did he write?  
John Green also wrote a science fiction book called Ender's Game. Would you like me to look up more on that?