Search:

I've went through two different dictionaries and found examples:

Harper Collins:

чей это ребёнок? - Whose child is this?

Lingvo:

чей это нож? — whose knife is it?

Well, IMHO, I think it's:

чья это книга.

<---Cheburashka told me so. Can't argue with a native speaker. Plus, he said if I didn't believe him...he'd claw my eyes out! *nervously glances...