Extremely compact soft X-ray lasers based on capillary discharges - Rocca, J.J.; Filevich, J.; Hammarsten, E.C.; Jankowska, E.; Benware, B.; Marconi, M.C.; Luther, B.; Vinogradov, A.; Artiukov, I.; Moon, S.; Shlyaptsev, V.N. (Nuclear Instruments & Methods in Physics Research Section A, 2003)