Q - don't be a pedant. Someone is trying to be helpful. There are plenty of so called Guests who are only interested in stirring up trouble. Let's be welcoming to the ones who are trying to join in with the spirit of the Mudcat. Most of us do not have the time (or the inclination) to check every mudcat thread before submitting a posting.
Okay - by all means ask for a source - that is useful information, but let's face it the Digitrad is a hotch potch of sources, some creditable and others still to be checked or corrected. It improves as time goes on, but it still has a long way to go before it will become what Dick and Susan originally envisaged.
Quack!
GtD.