Jenny, thank you for your help with my paper.
It's my pleasure if I have done something helpful to you.
I am really grateful for the reference books you offered me. But for the materials, I would not have written my paper so quickly.
It's nice of you to say so. I am interested in your paper and I happen to have some books on the topic.
Your books are important to me. Besides, you have given me some very good suggestions. I really thank you so much.
You are welcome.