I have spent far too long chasing wild geese tonight

Does anyone want to prove their superior Google-fu? According to one of my databooks, the lattice enthalpy of tin (IV) oxide is in the order of 11000 kJ mol^-1. Theory suggests that tin (IV) oxide should have a high lattice enthalpy because of being made of +4 and -2 ions, but that number is severely off the scale. The highest lattice enthalpy I know of is magnesium oxide, which is around 3800 kJ mol^-1 (although apparently beryllium oxide is ~4500 kJ mol^-1). I cannot find anything to prove if that's a typo or not. My other textbooks are obsessed with Group 1 & 2 compounds.

I don't actually need to know this, but now that the question's been raised, I won't be happy until I find out.