oppose woolwich attack is clearly the wp commoname for this incident in addition any reader who wouldn't recognise ' woolwich attack' as referring to this incident is clearly not going to know that 'death murder of lee rigby' refers to it either so it offers no advantage on that score quite the opposite infact to the uninitiated 'death murder of lee rigby' could refer to any number of incidents motives places whereas most reasonable people would assume ' woolwich attack' refers to some kind of attack in a place called woolwich that occurred in which is good enough as a starting point i don't recognise any of the other articles listed above as being about this sort of incident so it's hard to put any weight on that argument at all