I believe they took this link down, as the Structured Network has "graduated" from an element of the Impact Management Project into being the Impact Management *Platform* itself.

That said, the Wayback Machine allows us to access webpages that have been taken down. See https://web.archive.org/web/20211029050656/https://impactmanagementproject.com/impact-management/structured-network/

We'll change this in the text itself tomorrow, Thanks for catching this!