Multiple reports given to investigators who traveled to the area, a mention of it being reported in the media, and a map showing physical evidence.
So far I have not found where this encounter was reported in the media.
The investigators who traveled to the area are Mr S Briggs and Mr A Fiannaca, independent(?) ex members of the Perth UFO Research Group, as mentioned in ACOS Bulletin #2.
As mentioned at the end of the above Bulletin 3 article, there would be a follow up in Bulletin 4.
“When results are are hand, we will advise everyone” I await them.
A further addition of information was published in Bulletin 5 (March 1976)
Sources & Links:
ACOS Bulletin 3, September 1975
ACOS Bulletin 4, December 1975
ACOS Bulletin 5, March 1976.