The screenshot relates to the headline, but also, being at this link, it allows you into easy access to Lewis' work online.
Let's see. Out of copyright if dead before 1955. Marx, Shakespeare, Woodrow Wilson, J.P. Morgan. Whatever they wrote would be in public domain in Australia. The lifetime writings of Prescott Bush, no, he died in 1972, so it's not clear cut what copyright status might attach. Were you to want to consider reading the lifetime writings of Prescott Bush, you might need to meet your responsibility to check applicable copyright law. Stalin's writings, in Australia, are public domain but without access to both sets, you cannot tell where the ideas of Prescott Bush and Stalin coincided and where they diverged. As to government activity, procedurally vs ideologically, there may have been similarities and differences. I can only guess.