1. Salesforce Health Cloud Developer Guide: "Assign Health Cloud Permission Sets". The documentation explicitly states, "Assign the Health Cloud Foundation permission set to give users access to Health Cloud objects and features. To give users access to more Health Cloud features, assign the Health Cloud Standard permission set."
Source: Salesforce Help, Health Cloud Developer Guide, Section: "Post-Installation Tasks" > "Set Up Users" > "Assign Health Cloud Permission Sets".
2. Trailhead by Salesforce: "Health Cloud Administration" module, "Set Up Your Health Cloud Org" unit. This module details the setup process, including user configuration.
Source: Trailhead, Health Cloud Administration, Unit: "Set Up Your Health Cloud Org", Section: "Assign Health Cloud Permission Sets". The text confirms the necessity of assigning both the "Health Cloud Foundation" and "Health Cloud Standard" permission sets for user access.