Western Australia Government – WA.gov: “Authorisation to Supply or Administer a Poison [SARS-Cov-2 (COVID-19) Vaccine – Australian Defence Force (No 7) 2021”
Firstly, please be aware that only governments are able to use a domain name which ends with .gov or gov.xx where xx refers to the two character alphabetic country code. Examples are gov.uk (for the UK Government) and gov.au (for the Australian Government).

——
Now that is out of the way, the above screenshot was taken directly from the Western Australia Government Website. The screenshot has been annotated in red to draw your attention to the main points. The web page can be accessed directly on the Western Australia Website at:
https://www.wa.gov.au/government/publications/authorisation-supply-or-administer-poison-sars-cov-2covid-19-vaccine-australian-defence-force-no-7-2021
There is also a link on the website to download the actual document as shown in the above screenshot. The document is stated to be signed by the Western Australian Government Chief Health Officer, Dr Andrew Robertson.
Below is the download link to the document directly from the Western Australia ‘wa.gov‘ web site.
https://www.wa.gov.au/system/files/2021-09/Authorisation-to-supply-or-administer-a-poison-SARS-COV-2-COVID-19-Vaccine-Australian-Defence-Force-No7-2021.pdf
For your convenience the document can also be viewed below.