Weyl's theorem on metric number theory
Zeros of a quadratic form at squarefree points
Primitive lattice points in planar domains
Sums of two relatively prime kth powers
The distribution of k - free numbers
The Collected Works of Bernhard Riemann
(with G. Harman) Numbers with a large prime factor II
Numbers with (or without) a large prime factor in a given set.
Schaffer's determinant argument