Caldwell, Allen Max Planck Institute for Physics, Max Planck Society;
https://lt.org/publication/how-can-plasma-and-proton-beams-be-used-building-next-generation-particle-accelerators (Multimedia)
Caldwell, A. (2016). How Can Plasma and Proton Beams Be Used in Building Next Generation Particle Accelerators? doi:10.21036/LTPUB10171.