1. Design of robust PID controllers;Ackermann,2001
2. Discrete-time robust PID and three-term control;Ackermann,2002
3. The method of singular frequencies for robust design in an affine parameter space;Bajcinca,2001
4. A linear programming characterization of all stabilizing PID controllers;Ho,1997
5. PID controller synthesis free of analytical models;Keel,2005