You can access the Invitation Circular for NUS GC 2018 here: https://nusgeographychallenge.files.wordpress.com/2018/01/gc2018-invitation-circular-for-schools-official.pdf
The Invitation Circular provides a brief overview of NUS GC 2018, and details key information such as the competition dates. A physical copy and soft-copy has been physically mailed and emailed to all schools respectively.
Do note that registration for NUS GC 2018 closes on 1st February 2018 at 2359hrs. We look forward to seeing you at NUS GC 2018!
~ NUS GC 2018 Organising Commitee