Acquisition of modals

[Nikola Isabel Koch]

Can anybody help me with literature on children's acquisition of the
epistemic and deontic meaning of modals in German and English in
general, and the German modal "muessen" and the English modal "must" in
particular?

I am interested in which form is acquired first and in the semantic and,
particularly, in the syntactic explanation for the results.

Thank you very much.

Nikola Koch
UMass, Amherst / Universitaet Stuttgart