Papers re Stark's conjectures:

Euler systems and the conjectures of Stark

Base change for the conjecture of Brumer-Stark

Aligning Brumer-Stark elements into a Hecke character

Papers re average class numbers:

Average norms of j-invariants of Drinfeld modules

Distribution of minimal ideals in imaginary quadratic function fields

Papers on other topics:

The 2-divisibility of the class number of the real subfield of the p-cyclotomic number field

On the 2-ranks of Hilbert Class Fields

Stickelberger functions for non-abelian extensions of global fields