@InProceedings{IR-EE-RT_2008:014b, author = {Lasse M. Eriksson and Mikael Johansson},title = {Simple {PID} tuning rules for varying time-delay systems},booktitle = {Proceedings {IEEE} Conference on Decision and Control},pages = {1801-1807},year = {2007},month = December, address = {New Orleans, LA} }