I think this is wrong; despite the fact the ATP website agrees with it. The 2009 version of the ATP media guide is confused on this: it gives Cash's total as 7 titles on one page, but only 6 on another, omitting '83 Melbourne.
If you look at the ATP website, the '83 Melbourne draw is just a messed-up version of the '82 draw; at first glance it seems different, but only because the matches are in a different order: the scores of all matches are identical.
Anyone know anything more about this? Is there just a mistake in the draw webpage, or was there no '83 Melbourne tournament? Which page of the ATP guide is correct?
You're right, it is wrong. I also noticed this during my work. It's hard whether it was actually meant to be a '82 or '83 tournament, but the Media Guide says '82. I guess the made a mistake since the tournament was played during new-year it was double-counted for both years.