1. An outline of language-origins theory since the renaissance;Aarsleff;Ann. N.Y. Acad. Sci.,1976
2. Account of the organs of speech of the orang outang;Camper;Phil. Trans. R. Soc.,1779
3. On the nature of language;Chomsky;Ann. N.Y. Acad. Sci.,1976a
4. Hansen , O. 1978 The Genes of Universal Grammar, An Attempt in Biologicized Philosophy Thesis University of Lund