LIEBL, H Surface Science (OP), Max Planck Institute for Plasma Physics, Max Planck Society;
LIEBL, H. (1972). COAXIAL COMBINED ELECTROSTATIC OBJECTIVE AND ANODE LENS FOR MICROPROBE MASS ANALYZERS. VACUUM, 22(11), 619-621. doi:10.1016/0042-207X(72)90038-3.