1. Fortesque, T.R., Keshenbaum, L.S. & Udstie, B.E.: Implementation of Self-tuning Regulators with Variable Forgetting Factors. Automatica (17), 6. 1981.
2. Lehtomäki, K., Kortela U. & Luukkanen J.: New Estimation and Control Methods for Fuel Power in Peat Power Plants. VIII IFAC World Congress, Kyoto, Japan, 1981.
3. Lehtomäki, K., Wahlström, F., Luukkanen, J. & Kortela, U.: New Combustion Control Methods in Power Plants Burning Inhomogeneous Fuels, Fift Power Plant Dynamics, Control and Testing Symposium, March 21–23, 1983, Knoxville, Tennessee, USA.
4. Kortela, U., Salmelin, B. & Wahlström, F.: A hierarchical Control Strategy for Multi-Fuel Multi-Boiler Systems, Fift Power Plant Dynamics, Control and Testing Symposium, March 21–23, 1983, Knoxville, Tennessee, USA.