2009 with Esther Rinke. « Subject-inversion in Old French: Syntax and information structure”.
2008. “Child second language acquisition or successive first language acquisition?”.
2006. The Development of the Weaker Language in Bilingual First Language Acquisition.
2005. The Weaker Language of Bilinguals: A Case of Second Language Acquisition in Early Childhood?
2004. with Matthias Bonnesen. Die “Subjekt-Verb Inversion” in Interrogativkonstruktionen des gesprochenenFranzösischen: Zum Problem der syntaktischen Variation
2004. “The Bilingual Child”.
1998. Revisiting Universal Grammar.
1997. « L’acquisition de la négation en langue première ».
1994. Bilingual First Language Acquisition: French and German Grammatical Development
1990. Two First Languages: Early Grammatical Development in Bilingual Children (Studies in Languages Acquisition, No 10)
1989. “Early differentiation of languages in bilingual children” in Bilingualism across the lifespan: aspects of acquisition, maturity, and loss.