David Cassidy

Positronium hyperfine interval measured via saturated absorption spectroscopy.

A. Mills, A. P. Mills, H. Tom, 2012, Physical review letters.

Efficient production of Rydberg positronium.

A. Mills, A. P. Mills, H. Tom, 2012, Physical review letters.

The production of molecular positronium

A. Mills, A. P. Mills, D. Cassidy, 2007, Nature.