The Queensland Constitution - the creation of Queensland as a separate colony.
A Bill to Consolidate the Laws relating to the Constitution of the Colony of Queensland.
The three volume work Opinions of Attorneys-General of the Commonwealth of Australia (published between 1981 and 2013) comprises legal advice provided to the Commonwealth government between 1901 and 1945, from Federation and the creation of the Commonwealth to shortly after the Second World War. These opinions consider many constitutional issues, and are an invaluable historical resource.
The Opinions are no longer accessible online however hard copy is still accessible through Trove and various Universities.
Constitution Education Fund Australia - an independent, non partisan and non-profit organisation committed to increasing public understanding and appreciation of the Constitution, its history and contemporary relevance.