- https://stackoverflow.com/questions/43758649/how-to-implement-attribute-based-access-control-abac-in-php
- https://docs.wso2.com/display/AM1100/Enabling+Role-Based+Access+Control+Using+XACML
- https://docs.wso2.com/display/IS530/Configuring+Access+Control+Policy+for+a+Service+Provider
- https://docs.wso2.com/display/IS530/Role-based+Permissions
- https://stackoverflow.com/questions/46430477/policy-entitlement-xacml-in-wso2-identity-server-with-wso2-api-manager