1. Alexiadou, Artemis, and Elena Anagnostopoulou. 1998. Parametrizing AGR: word order, V-movement & EPP checking. Natural Language & Linguistic Theory 16: 491–539.
2. Alexiadou, Artemis, Monika Rathert, and Arnim von Stechow, eds. 2003. Perfect explorations. Berlin: Mouton de Gruyter.
3. Baker, Mark C. 1988. Incorporation: a theory of grammatical function changing. Chicago: University of Chicago Press.
4. Barbosa, Pilar. 1995. Null Subjects. PhD dissertation, MIT.
5. Barbosa, Pilar. 2006. Two kinds of subject pro? Manuscript, Universidade do Minho.