Fig. 1
From: What can urban mobility data reveal about the spatial distribution of infection in a single city?
The SA3 and SA4 regions that comprise metropolitan Melbourne. Each SA4 is shown in a different colour, and contains 3–7 SA3s. Each SA3 is identified by a 5-digit number, beginning with the SA4 code (shown in the figure legend) and followed by a number between 1 and N (where the SA4 contains N SA3s). For example, the central business district (CBD) has the ID 20604; it is located in the Inner (206) SA4, which contains 7 SA3s, and is identified here by the digit “4”