Jeremy Black. What If? Counterfactualism and the Problem of History. London: Social Affairs Unit, 2008. What if I confused this book with an expanded edition under a different title? I'd probably end up ordering that edition too.
John Connor, Peter Stanley and Peter Yule. The War at Home. The Centenary History of Australia and the Great War, volume 4. South Melbourne: Oxford University Press, 2015. It's possible that I bought this in part because I (or my ego) wanted to see if it cited me. But only in part. With sections covering politics, society and economy, there's something here for everyone [who is interested in the Australian home front in the First World War].
Leigh Edmonds. Australia Takes Wing 1900-1939. Flight in Australia, volume 1. Ballarat: BHS Publishing, 2015. I actually bought this last year, but forgot to list it here, I think because it's an ebook. The focus is very much on civil aviation, which Leigh argues has been (and is) more important here than in other countries with similar-sized populations and economies, by virtue of the practically unique geographical problems encountered in Australia. I'm looking forward to the next volume; you can buy this one here.