Question

Which is the most important reference source when writing a novel set in the early twentieth century?



fashion magazines of that period




maps used during that period




personal diaries of people from that period




ledgers of banks and financial institutions from that period

Answer 1

I want to say either diaries or fashion magazines. Diaries are much more story like and could be a little lathered up for lack of a better word. However I would go with fashion magazines, which talk about whatever's popular at the time, giving you a quick general outlook on the time period.