D M Wallen was the author of these articles. He completed some great research. I'll see if I can prepare a page showing that flaw.
In regard to the book and magazines you acquired, I have spares of 'The Australian Philatelist' Vol 1, No 4, Vol 1 no 5 and the 1991 yearbook (this last the final issue).
Yours for the asking, Rod.
For all readers, that series of just 12 issues in a phenomenal philatelic resource, particularly in regard to Richard Breckon's analysis of Australian postage rates from 1901 to 1966.
As an example, I had tried to decipher the way this cover was taxed:
A member on a Facebook page explained to me that outwards mail from Tasmania was not subject to air mail charges from October, 1937 (it still applied to inward mail to Tasmania until 1959). This information was confirmed in Vol 2, No 2 of 'The Australian Philatelist'.
Rod Perry has limited supply of all issues. Enquire through www.rap.com.au.