The citation of Port of Melbourne Authority v Anshun Pty Ltd (1981) 147 CLR 589 shows that this case is reported in the Commonwealth Law Reports.
These reports include decisions of the High Court of Australia (and, in the past, those decisions of the Judicial Committee of the Privy Council when it heard appeals from Australia).
In most circumstances decisions reported in the CLR are binding on all lower level Australian courts, including the NSW Court of Appeal.
NOTE: Decisions of the Judicial Committee of the Privy Council made after 1986 are not binding on Australian courts.