This one is just a placemarker. In our book Temporal Data and the Relational Model (Morgan Kaufmann, 2003), Hugh Darwen, Nikos Lorentzos, and I show that several further kinds of redundancy can arise in connection with temporal data, and we propose a number of new design principles and techniques for dealing with them. In particular, that book is the source of the new normal form 6NF (discussed in Chapter 13), though it’s important to understand that 6NF has an extended definition (and is “even more relevant”) in the temporal context.