Adelaide office server and development
Australian Academic and Research Network, www.aarnet.edu.au.
Authorised users only. This is telecommunications carrier equipment; there are substantial penalties for misuse. Use of this computer is monitored and recorded.
Some websites list yoyo.aarnet.edu.au as a public NTP server. It used to be, twenty years ago when the Internet was a much smaller place.
It isn't anymore. There's no need. GPS receivers make cheap high-stratum time sources so there's no justification for any enterprise to allow NTP to pass its firewall.
The current list of public NTP servers is at support.ntp.org/bin/view/Servers/WebHome. Please link to it rather than copying it; after all, that's how you came to find the ancient document refering to yoyo in the first place.