1. Dryer M, Haspelmath M, eds (2011) The World Atlas of Language Structures Online (Max Planck Digital Library, Munich).
2. Comrie B (1981) Language Universals and Linguistic Typology (Blackwell, Oxford).
3. Mallinson G Blake BJ (1981) Language Typology (North-Holland, Amsterdam).
4. Syntactic Typology and Linearization
5. The SOV >62; … >62; OSV frequency hierarchy