Permanent establishment: fixed place or dependent agent presence creates taxable business nexus when activities occur for a sustained period. The provision defines permanent establishment as a fixed place of business including examples (management, branch, office, factory, workshop, warehouse, store, resource installations) and treats sustained construction or supervisory activities and services related to mineral oil operations as creating a permanent establishment. It excludes solely preparatory or auxiliary activities (storage, display, stock for processing, purchasing, information collection). Dependent-agent rules attribute a permanent establishment where a person habitually concludes contracts, maintains delivery stock, or secures orders; independent agents operating in the ordinary course do not create such presence, nor does corporate control alone.