It says "we ask", not "you have to". I'd say it's open to interpretation that this is an informal request and not legally binding. Also I do want to open the ca

It says "we ask", not "you have to". I'd say it's open to interpretation that this is an informal request and not legally binding. Also I do want to open the can of worms and say that whoever doesn't even have the respect to include a citation on request when using someone else's work should just write everything themselves.