1. Åström, K.J. and Hägglund, T. (1984). Automatic tuning of simple regulators with specification on phase and amplitude margins. Automatica, Vol. 20, pp. 645-651.
2. Åström K.J. and Hägglund, T. (1995). PID Controllers: Theory, Design and Tuning. Research Triangle Park, NC: Instrumental Society of America.
3. Åström K.J., and Hägglund, T. (2001). The future of PID control, Control Engineering Practise, Vol. 9, pp. 1163-1175.
4. Åström, K.J. and Murray, R.M. (2008). Feedback Systems. Research Triangle Park, NC: Instrumental Society of America.
5. Kučera, V. (1993). Diophantine equations in control - A survey, Automatica, Vol. 29, No. 6, pp. 1361-75.