title: Comment on "Spaser action, loss compensation, and stability in plasmonic systems with gain".
authors.affiliation: The Blackett Laboratory, Department of Physics, Imperial College London, London, SW7 2AZ, United Kingdom.
authors.forename: J B
authors.initials: JB
authors.lastname: Pendry
authors.forename: S A
authors.initials: SA
authors.lastname: Maier