I recorded this video yesterday morning on some possible reading/re-reading for the Australia Day long weekend: John Maynard Keynes’s Economic Consequences of the Peace, now in its centennial year. You can find the book’s full text online. The book was published in the UK in late 1919 but in the United States in 1920, which is why the publication date is often given as 1920. Keynes’s preface to the book is dated November 1919.
Regarding books directly relevant to Australia Day, I’d recommend Rob Mundle’s The First Fleet and Michael Pembroke’s Arthur Phillip: Sailor, Mercenary, Governor, Spy.