Will a PCI Express x1 card work in a PCI Express x16 slot.?

I don't want any answers about the version compatibility or any answers based on version compatibility. I just want to know whether a PCI Express x1 card will work in a PCI Express x16 slot ??? because I heard somewhere else, that it would work. So I need your istance !!! I again repeat that I don't want answers based on the version compatibility, but I want answers based on the slot type and card type compatibility. Please don't provide misguiding answers. Please verify somewhere else for the correct answers, if you don't know the answer and give me your istance. Bye !!!