User:SOTO/Forum Archive/Inclusion debates/@comment-5545417-20150725190725/@comment-10983683-20150820213722
From Tardis Wiki, the free Doctor Who reference
I think the most damning evidence in favor of the backups comes from Four Doctors. In part one, Eleven leaves for a bit to buy some French comics. The backup in that issue, The Doctor Shops for Comics, shows him going to a Parisian newsstand to do just that, with some direct references to what's going on in the main story. Then, in part two, Eleven runs past and remarks on the very same newsstand. I think this shows very clear intent for the backups to be "in-universe".