Primary source: wals.info/chapter/81
Verified locator: WALS chapter 81, §1: specified transitive clauses, six logically possible dominant orders, operational A/P participant definitions and no-dominant-order category.
Verified locator: Author university-hosted research statement: typology, syntax, documentation, cross-language word-order database and atlas contribution. Named portrait link MatthewDryer.jpg.
Primary source: wals.info/
Verified locator: Provider project description, publication history, feature/chapter navigation and How to cite WALS Online. Cite a specific chapter for its data.