HARRI EHTAMO	
P.O. Box 1100, 02015 HUT, Finland	
PROFESSOR	Phone  +358 9 451 3058, fax -3096	
SYSTEMS ANALYSIS LABORATORY	Mobile  +358 50 341 6853	
HELSINKI UNIVERSITY OF TECHNOLOGY	ehtamo@hut.fi   www.sal.hut.fi	

January, 2009

LIST OF PAPERS AND PUBLICATIONS 

Harri Ehtamo
The papers deal mostly with optimization and game theory models and numerical algorithms for them. The last conference papers deal with the research under application.

I 	PAPERS IN JOURNALS, BOOK REVIEWS, EDITED BOOKS, SOFTWARE (40 refs,)
II	PAPERS IN CONFERENCE PROCEEDINGS (36 refs.)
III	RESEARCH REPORTS (18 refs.)
IV	ARTICLES IN FINNISH (4 refs.)

I  PAPERS IN JOURNALS

(I:36)		M. Ruokokoski, H. Ehtamo, J. Sorsa and M.-L. Siikonen: Passanger allocation to capasitated elevator problem. (Working paper).
 (I:35)		J.S. Sorsa, H. Ehtamo, M.-L. Siikonen, T. Tyni and J. Ylinen: Elevator dispatching as stochastic bilevel programming problem . (Working paper).
 (I:34)		K. Berg and H. Ehtamo: Learning in optimal screening problem when utility functions are unknown.  (Submitted manuscript).
 (I:33)		H. Ehtamo and M. Kitti: Osborne’s cartel maintaining rule revisited. (Submitted manuscript).
 (I:32)		H. Ehtamo, K. Berg and M. Kitti: An adjustment scheme for nonlinear pricing problem with two buyers. (To appear in European Journal of Operational Research).
 (I:31)		M. Kitti and H. Ehtamo: Adjustment of an affine contract with fixed-point iteration. (To appear in  Journal of Optimization Theory and Applications, January 2009).
(I:30)		M. Kitti and H. Ehtamo: Analysis of the constraints proposal method for two-party negotiations. European Journal of Operational Research, Vol. 181, No. 2, 2007, pp. 817-827.
(I:29)		H. Ehtamo, M. Kitti and R.P. Hämäläinen: Recent studies on incentive design problems in game theory and management science, In: Optimal Control and Differential Games, Essays in Honor of Steffen Jörgensen, Georges Zaccour (ed.), Kluwer, Boston, 2003, pp. 121-134.
(I:28)		J. Sorsa, M-L. Siikonen and H. Ehtamo: Optimal control of double-deck elevator group using genetic algorithm, International Transactions in Operational Research, Vol. 10, No. 2, February 2003, pp. 1-12.
(I:27)		T. Raivio and H. Ehtamo: Discretization, nonlinear and bilevel programming in pursuit-evasion games, Game Theory and Applications, Vol. 7, L.A. Petrosjan and V.V. Mazalof (eds.), Nova Science Publishers, New York, 2002, pp. 131-146.
(I:26)		H. Ehtamo and R.P. Hämäläinen: Interactive multiple-criteria methods for reaching Pareto optimal agreements in negoatiations, Group Decision and Negotiation, Vol. 10, No. 6, November 2001, pp. 475-491.
(I:25)		R.P. Hämäläinen, E. Kettunen. M. Marttunen and H. Ehtamo: Evaluating a framework for multi-stakeholder decision support in water resources management, Group Decision and Negotiation, Vol. 10, No. 4, pp. 331-353, 2001. 
(I:24)		P. Heiskanen, H. Ehtamo and R.P. Hämäläinen: Constraint proposal method for computing Pareto solutions in multi-party negotiations, European Journal of Operational Research, Vol. 133, No 1, August 2001, pp. 44-61.
(I:23)		H. Ehtamo, E. Kettunen and R.P. Hämäläinen: Searching for joint gains in multi-party negotiations, European Journal of Operational Research, Vol. 130, No. 1, February 2001, pp. 54-69.
(I:22)		H. Ehtamo and T. Raivio: On applied nonlinear and bilevel programming for pursuit-evasion games, Journal of Optimization Theory and Applications, Vol. 108, No. 1, January 2001, pp. 65-96.
(I:21)		T. Raivio and H. Ehtamo: Visual aircraft identification as a pursuit-evasion game, Journal of Guidance, Control, and Dynamics, Vol. 23, No. 4, 2000 pp. 701-708.
(I:20)		T. Raivio and H. Ehtamo: On numerical solution of a class of pursuit-evasion games, Annals of the International Society of Dynamic games, Vol. 5. In: Advances in Dynamic Games and Applications, J.A. Filar, V.Gaitsgory, K. Mizukami (eds.), Birkhäuser, Boston, 2000, pp. 177-192.
(I:19)		H. Ehtamo, R.P. Hämäläinen, P. Heiskanen, J. Teich, M. Verkama and S. Zionts: Generating Pareto solutions in two-party negotiations by adjusting artificial constraints, Management Science, Vol. 45, No. 12, December 1999, pp. 1697-1709
(I:18)		H. Ehtamo, M. Verkama and R.P. Hämäläinen: How to select fair improving directions in a negotiating model over continuous issues, IEEE Transactions on Systems, Man, and Cybernetics - Part C: Applications and Reviews, Vol. 29, No. 1, 1999, pp. 26-34.
(I:17)		K. Virtanen, H. Ehtamo, T. Raivio and R.P. Hämäläinen: VIATO - Visual interactive aircraft trajectory optimization, IEEE Transactions on Systems, Man, and Cybernetics - Part C: Applications and Reviews, Vol. 29, No. 3, 1999, pp. 409-421.
(I:16)	M. Verkama, H. Ehtamo and R.P. Hämäläinen: Distributed computation of Pareto solutions in N-player games, Mathematical Programming, Vol. 74, 1996, pp. 29-45.
(I:15)	H. Ehtamo, M. Verkama and R.P. Hämäläinen: On distributed computation of Pareto solutions for two decision makers, IEEE Transactions on Systems, Man, and Cybernetics - Part A: Systems and Humans, Vol. 26, No. 4, 1996, pp. 498-503.
(I:14)	H. Ehtamo and R.P. Hämäläinen: Credibility of linear equilibrium strategies in a discrete time fishery management game, Group Decision and Negotiation, Vol. 4, 1995, pp. 27-37.

(I:13)	H. Ehtamo and J. Ruusunen: Contracting in dynamic games, Group Decision and Negotiation, Vol. 4, 1995, pp. 59-69.

(I:12) 	H. Ehtamo and J. Ruusunen: On independence of irrelevant alternatives and dynamic programming in dynamic bargaining games, Annals of the International Society of Dynamic Games, Vol. 3. In: New Trends in Dynamic Games and Applications, G.J. Olsder (ed.), Birkhäuser, Boston, 1995, pp. 395-408.

(I:11)		H. Ehtamo and T. Raivio: Numerical solution of minimum time climb trajectories, CSC News (Center for Scientific Computing), Vol. 6, No. 3, 1994, pp. 15-18.

(I:10)	M. Verkama, R.P. Hämäläinen and H. Ehtamo: Modeling and computational analysis of reactive behavior in organizations, in: Computational Organization Theory, Kathleen M. Carley and Michael J. Prietula (eds.), Lawrence Erlbaum Associates, Hillsdale, NJ, 1994, pp. 161-177.
(I:9)	H. Ehtamo and R.P. Hämäläinen: A cooperative incentive equilibrium for a resource management problem, Journal of Economic Dynamics and Control, Vol. 17, No. 4, 1993, pp. 659-678. 
(I:8)	M. Verkama, R.P. Hämäläinen and H. Ehtamo: Multi-agent interaction processes: From oligopoly theory to decentralized artificial intelligence, Group Decision and Negotiation, Vol. 1, No. 2, 1992, pp. 137-159.
(I:7)	J. Ruusunen, H. Ehtamo and R.P. Hämäläinen: Dynamic cooperative electricity exchange in a power pool,  IEEE Transactions on Systems, Man, and Cybernetics, Vol. 21, No. 4, July/August 1991,  pp.758-766.
(I:6)	H. Ehtamo and R.P. Hämäläinen: Incentive strategies and equilibria for dynamic games with delayed information, Journal of Optimization Theory and Applications, Vol. 63, No. 3, December 1989, pp. 355-369.
(I:5)	H. Ehtamo, J. Ruusunen and R.P. Hämäläinen: A hierarchical approach to bargaining in power pool management, IEEE Transactions on Automatic Control, Vol. AC-34, No.6, June 1989, pp. 666-669.
(I:4)	H. Ehtamo, J. Ruusunen and R.P. Hämäläinen: On the computation of the Nash bargaining solution, Computers and Mathematics with Applications, Vol. 18, No. 1-3, 1989, pp. 189-193.
(I:3)	H. Ehtamo, J. Ruusunen, V. Kaitala and R.P. Hämäläinen: Solution for a dynamic bargaining problem with an application to resource management, Journal of Optimization Theory and Applications, Vol.59, No.3, December 1988, pp. 391-405.
(I:2)		H. Ehtamo and R.P. Hämäläinen: On incentive design for dynamic decision problems, Journal of  Economic Dynamics and Control, Vol. 10, 1986, pp. 41-43.
(I:1)	H. Ehtamo, J. Lindfors and L. McLerran: Can the fluctuations in Head-on ultrarelativistic nuclear    collicions be large?, Zeitschrift fur Physik C, Particles and Fields, Vol. 18, 1983, pp. 341-348.

BOOK REVIEWS
(1)		H. Ehtamo: Dynamic noncooperative game theory, by Tamer Basar and Geert Jan Olsder, Book review, Journal of Economic Dynamics and Control, Vol. 21, 1997, pp. 1113-1116.  

EDITED BOOKS
(2)		R.P. Hämäläinen and H. Ehtamo, (eds.): Dynamic games in economic analysis, Lecture Notes in Control and Information Sciences, Vol. 157, Springer-Verlag, 1991. 
(1)		R.P. Hämäläinen and H. Ehtamo, (eds.): Differential games - Developments in modeling and computation, Lecture Notes in Control and Information Sciences, Vol. 156, Springer-Verlag, 1991.

SOFTWARE DESIGN
(1)		E. Kettunen, R.P. Hämäläinen and H. Ehtamo: Joint Gains - Negotiation Support in the Internet, Systems Analysis Laboratory, Helsinki University of Technology, 1998. (www.jointgains.hut.fi)

II  PAPERS IN CONFERENCE PROCEEDINGS
(II:36)	K. Berg and H. Ehtamo: Multidimensional screening: Online computation and limited information. (To appear in Proc. of the 10th International Conference on Electronic Commerce, Innsbruck, Austria, August 18-22, 2008).

(II:35)	H. Ehtamo, S. Heliövaara, S. Hostikka and T. Korhonen: Modeling evacuees’ exit selection with best response dynamics, (To appear in Pedestrian and Evacuation Dynamics 2008, Andreas Schadschneider (ed.), Springer-Verlag, December 2008.
(II:34)	T. Korhonen, S. Hostikka, S. Heliövaara and H. Ehtamo: FDS+Evac: Modelling social interactions in fire evacuation, Proc. of the 7th International Conference on Performance-Based Codes and Fire Safety Design Models, New Zeland, April 16-18, 2008, pp. 241-250.
(II:33)	T. Korhonen, S. Hostikka, S. Heliövaara and H. Ehtamo: Integration of an agent based evacuation simulation and the state-of-the-art fire simulation, Proc. of the 7th Asia-Oceania Symposium on Fire Science and Technology, September 20-22, 2007, Hong Kong.
(II:32)	T. Korhonen, S. Hostikka, S. Heliövaara, H. Ehtamo and K. Matikainen: FDS+Evac: Evacuation module for fire dynamics simulator, Proc. of the Interflam 2007: 11th International Conference on Fire Science and Engineering, London, September 3-5, 2007, pp. 1443-1448.
(II:31)	H. Ehtamo, R.P. Hämäläinen and V. Koskinen: An e-learning module on negotiation analysis, Proc. of the 37th Annual Hawaii International Conference on System Sciences, IEEE Computer Society Press, Hawaii, January 5-8, 2004.
(II:30)	H. Ehtamo and R.P. Hämäläinen: Sensitivity analysis of the jointly improving direction method, Proc. of the Group Decision and Negotiation 2001, F. Ackermann and Gert-Jan de Vreede (eds.), La Rochelle, France, June 4-7, 2001, pp. 123-125.
(II:29)	H. Ehtamo and R.P. Hämäläinen: Searching for joint gains in multi-party negotiations, Proc. of the International Workshop on Decision and Control in Management Sciences, in Honor of Professor Alain Haurie, Montreal, Canada, October 19-20,  2000, pp. 245-250. 
(II:28)	R.P. Hämäläinen, E. Kettunen, M. Marttunen and H. Ehtamo: Towards decision and negotiation support in multi-stakeholder development of lake regulation policy, Proc. of the 32nd Annual Hawaii International Conference on System Sciences, January 5-8, 1999. IEEE Computer Society Press. 
(II:27)	H. Ehtamo and T. Raivio: A feasible direction method for saddle point problems, Proc. of the 8th International Symposium on Dynamic Games and Applications, Maastricht, The Netherlands, July 5-8, 1998, pp. 184-188.
(II:26)	T. Raivio, K. Virtanen, H. Ehtamo and R.P. Hämäläinen: Microcomputer simulation of optimal flight paths, Proc. of the EUROSIM’98 Simulation Congress, K. Juslin (ed.), April 14-15, 1998, Espoo, Finland, Vol. 2, pp. 288-289.
(II:25)	H. Ehtamo, M. Verkama and R.P. Hämäläinen: How to select fair improving directions in a negotiation model over continuous issues, Proc. of the 1997 IEEE International Conference on Systems, Man, and Cybernetics, Orlando, Florida, October 12-15,1997, Vol. 4, pp. 3466-3471. 
(II:24)	T. Raivio and  H. Ehtamo: Applying nonlinear programming to a complex pursuit-evasion problem, Proc. of the 1997 IEEE International Conference on Systems, Man, and Cybernetics, Orlando, Florida, October 12-15, 1997, Vol. 2, pp. 1548-1551.
(II:23)	K. Virtanen, H. Ehtamo, T. Raivio and R.P. Hämäläinen: VIATO - Visual interactive aircraft trajectory optimization, Proc. of the 1997 IEEE International Conference on Systems, Man, and Cybernetics, Orlando, Florida, October 12-15, 1997, pp. Vol. 3, pp. 2280-2285.
(II:22)	R.P. Hämäläinen, E. Kettunen and H. Ehtamo: Game modeling and coordination processes for two-level multi-agent systems, Proc. of the Sixteenth IASTED International Conference on Modelling, Identification and Control, Innsbruck, Austria, February 17-19, 1997, pp. 234-240.
(II:21)	T. Raivio, H. Ehtamo and R.P. Hämäläinen: A decomposition method for a class of pursuit-evasion games, Proc. of the Seventh International Symposium on Dynamic Games and Applications, Kanagawa, Japan, December 16-18, 1996, Vol. 2, pp. 784-795.
(II:20)	H. Ehtamo and K. Virtanen: Interactive aircraft trajectory optimization and simulation, Proc. of the European Simulation Multiconference, Budapest, June 1996, pp. 156-160.

(II:19)	T. Raivio, H. Ehtamo and R.P. Hämäläinen: Simulating the worst case prediction error of systems trajectories, Proc. of the European Simulation Multiconference, Budapest, June 1996, pp. 299-303.
(II:18)	T. Raivio, H. Ehtamo and R.P. Hämäläinen: Aircraft trajectory optimization using nonlinear programming, Proc. of the 7th IFIP TC7 Conference on System Modelling and Optimization, July 10-14, 1995. Prague, Czech Republic, J. Dolezal and J. Fidler (eds.), Chapman & Hall, 1996, pp. 435-441.
(II:17)	H. Ehtamo and J. Ruusunen: An axiomatic bargaining approach for sharing divisible goods, in: Multidisciplinary Views on Strategic Interactions, Matti Wiberg (ed.), University of Turku, Department of Political Science, Studies on Political Science, No. 14, 1996, pp. 85-98.
(II:16)	H. Ehtamo, M. Verkama and R.P. Hämäläinen: How to select fair improving directions in a negotiation model over continuous issues, Proc. of the Decision Sciences Institute 1995 Annual Meeting, Boston,  Massachusetts, November 20-22, 1995, Vol. 2, pp. 549-551.
(II:15)	H. Ehtamo, M. Verkama and R.P. Hämäläinen: Successive proposals: An approach to the computation and enforcement of efficient agreements, in: Multicriteria Analysis, Joao Climaco (ed.), Proc. of the XIth International Conference on Multiple Criteria Decision Making, Coimbra, Portugal, August 1-6, 1994, pp. 356-365. 
(II:14)	H. Ehtamo, T. Raivio and R.P. Hämäläinen: A method to generate trajectories for minimum time climb, Proc. of the Sixth International Symposium on Dynamic Games and Applications, St-Jovite, Quebec, Canada, July 13-15, 1994, pp. 175-183.
(II:13)	H. Ehtamo, M. Verkama and R.P. Hämäläinen: On distributed computation of Pareto solutions in a duopoly, Proc. of the  IEEE International Conference on Systems, Man, and Cybernetics, Le Touquet, France, October 17-20, 1993, Vol. 1, pp. 197-202.
(II:12)	H. Ehtamo and R.P. Hämäläinen: On the credibility of linear equilibrium strategies in discrete time fishery management games, Proc. of the Fifth International Symposium on Dynamic Games and Applications, Grimentz, Switzerland, July 15-17, 1992.
(II:11)	H. Ehtamo, M. Verkama and R.P. Hämäläinen: On contracting under incomplete information using linear proposals, Proc. of the Fifth International Symposium on Dynamic Games and Applications, Grimentz, Switzerland, July 15-17, 1992.
(II:10)		H. Ehtamo, J. Ruusunen and R.P. Hämäläinen: On intertemporal cooperation - A dynamic stochastic problem with nonadditive group utility function, in: Dynamic Games in Economic Analysis, R.P. Hämäläinen and H. Ehtamo (eds.), Lecture Notes in Control and Information Sciences, Vol. 157, Springer-Verlag, 1991, pp. 88-94. 

(II:9)  	J. Ruusunen, H. Ehtamo and R.P. Hämäläinen: Dynamic cooperative electricity exchange in a power pool, Proc. of the IEEE Conference on Systems, Man, and Cybernetics, Cambridge, Massachusetts, November 14-17, 1989, pp. 268-273.
(II:8)  	H. Ehtamo, J. Ruusunen and R.P. Hämäläinen:  On a class of cooperative feedback solutions for differential games, in: Dynamic Modelling and Control of National Economies 1989, Selected Papers from the 6th IFAC Symposium, Edinburgh, UK, 27-29 June, 1989, pp. 33-35.
(II:7)  	H. Ehtamo, J. Ruusunen and R.P. Hämäläinen: Repeated bargaining under uncertainty, in: Differential Games and Applications, T. Basar and P. Bernhard (eds.), Lecture Notes in Control and Information Sciences, Vol. 119, Springer-Verlag, 1989, pp. 178-185.
(II:6)  	J. Ruusunen, H. Ehtamo and R.P. Hämäläinen: Bargaining with dynamic information, Proc. of the Bellman Continuum Workshop 1988, Modelling and Control of Systems in Engineering, Quantum Mechanics, Economics, and Biosciences, A. Blaquiére (ed.), Lecture Notes in Control and Information Sciences, Vol. 121, Springer-Verlag, 1989, pp. 349-354.
(II:5)	H. Ehtamo, J. Ruusunen and R.P. Hämäläinen: The formulation of the Nash bargaining problem as a hierarchical control problem, in: Operations Research Proceedings 1987, H. Schellhaas et.al. (eds.), Springer-Verlag, 1988, pp. 526-533. 
(II:4)	H. Ehtamo, J. Ruusunen and R.P. Hämäläinen: On the computation of the Nash bargaining solution with an energy management example, Proc. of The 26th IEEE Conference on Decision and Control, Los Angeles, CA, December 1987, pp. 263-266.
(II:3)  	H. Ehtamo and R.P. Hämäläinen: On affine incentives for dynamic decision problems, in: Dynamic Games and Applications in Economics, T. Basar (ed.), Lecture Notes in Economics and Mathematical Systems, Vol. 265, Springer-Verlag, Vol. 265, 1986, pp. 47-63.
(II:2)  	H. Ehtamo and R.P. Hämäläinen: Construction of optimal affine incentive strategies for linear quadratic Stackelberg games, Proc. of The IEEE Conference on Decision and Control, Vol. 2, Fort Lauderdale, December 1985, pp. 1093-1098.   
(II:1)  	H. Ehtamo, R.P. Hämäläinen and V. Kaitala: On incentive solutions for linear-quadratic Stackelberg games, Proc. of The American Control Conference, Vol. 2, Boston, June 19-21, 1985, pp. 1109-1113.  

III RESEARCH REPORTS
(III:18)	M. Verkama, H. Ehtamo and R.P. Hämäläinen: Distributed computation of Pareto solutions in N-player games, Helsinkin University of Technology, Systems Analysis Laboratory, Research Reports A53, October 1994.

(III:17)	H. Ehtamo, M. Verkama and R. P. Hämäläinen: On distributed computation of Pareto solutions for two decision makers, Helsinkin University of Technology, Systems Analysis Laboratory, Research Reports A52, October 1994.	

(III:16)	H. Ehtamo, M. Verkama and R.P. Hämäläinen: Negotiating efficient agreements over continuous issues, Helsinki University of Technology, Systems Analysis Laboratory, Research Reports A51, June 1994.
(III:15)	H. Ehtamo and J. Ruusunen: Intertemporal bargaining and dynamic consistency, Helsinki University of Technology, Systems Analysis Laboratory, Research Reports A48, 1993.
(III:14)	M. Verkama, R. P. Hämäläinen and H. Ehtamo: Multi-agent interaction processes: From oligopoly theory to decentralized artificial intelligence, Helsinkin University of Technology, Systems Analysis Laboratory, Research Reports A42, November 1991.
	
(III:13)	H. Ehtamo and J. Ruusunen: An intertemporal bargaining model, Helsinki University of Technology, Systems Analysis Laboratory, Research Reports A35, 1990.

(III:12)	R.P. Hämäläinen and H. Ehtamo, Eds.: Fourth International Symposium on Differential Games and Applications - Preprints Vol. II, Helsinki University of Technology, Systems Analysis Laboratory, Research Reports A33, 1990.  

(III:11)	R.P. Hämäläinen and H. Ehtamo, Eds.: Fourth International Symposium on Differential Games and Applications - Preprints Vol. I, Helsinki University of Technology, Systems Analysis Laboratory, Research Reports A32, 1990.  

(III:10)	J. Ruusunen, H. Ehtamo and R. P. Hämäläinen: Dynamic cooperative electricity exchange in a power pool, Helsinkin University of Technology, Systems Analysis Laboratory, Research Reports A30, April 1989.

(III:9)	H. Ehtamo: Incentive strategies and bargaining solutions for dynamic decision problems, Doctoral Thesis, Helsinki University of Technology, Systems Analysis Laboratory, Research Reports A29, 1988.

(III:8)	H. Ehtamo: On closed-loop epsilon-strategies for differential games, Helsinki University of Technology, Systems Analysis Laboratory, Research Reports A28, 1988.  

(III:7)	H. Ehtamo and R. P. Hämäläinen: A cooperative incentive equilibrium for a resource management problem, Helsinkin University of Technology, Systems Analysis Laboratory, Research Reports A25, June 1988.

(III:6)		H. Ehtamo, J. Ruusunen and R.P. Hämäläinen: On the computation of the Nash bargaining solution with an energy management example, Helsinki University of Technology, Systems Analysis Laboratory, Research Reports A20, May 1987.
(III:5)	H. Ehtamo, J. Ruusunen, V. Kaitala and R.P. Hämäläinen: Solution for a dynamic bargaining problem with an application to resource management, Helsinkin University of Technology, Systems Analysis Laboratory, Research Reports A17, June 1986.

(III:4)		H. Ehtamo and R. P. Hämäläinen: On affine incentives for dynamic decision problems, Helsinki University of Technology, Systems Analysis Laboratory, Research Reports A14, June 1985.
(III:3)		H. Ehtamo and R.P. Hämäläinen: Construction of optimal affine incentive strategies for linear-quadratic Stackelberg games, Helsinki University of Technology, Systems Analysis Laboratory, Research Reports A12, March 1985.  
(III:2)	H. Ehtamo: On classical Yang-Mills fields with time-dependent sources, Research Institute for Theoretical physics, University of Helsinki, Preprint Series in Theoretical physics, No. HU-TFT-82-49, 1982.

(III:1)	H. Ehtamo: Effective potential in gauge field theories, Licentiate Thesis, University of Helsinki, Department of Theoretical Physics, 1980. A shortened version Effective potential of tachyon field in 1+1 dimension, Research Institute for Theoretical Physics, University of Helsinki, Preprint Series in Theoretical Physics, No. HU-TFT-81-2, 1982.  

IV  ARTICLES IN FINNISH
(IV:4)		H. Ehtamo: Optimointi – Mallintamista, matematiikkaa, geneettisiä algoritmeja, Polysteekki, 1/2000, ss. 12-14. INFORS, 1/2000, ss. 15-20.

(IV:3)		H. Ehtamo: Parantavien suuntien menetelmä, Monitavoitteisen päätäksenteon mallit vesistön säännöstelyssä, Raimo P. Hämäläinen (toim.), Helsinki University of Technology, Systems Analysis Laboratory, Research Reports, No. B21, June 1997, pp. 58-63.

(IV:2)		H. Ehtamo ja P. Miettinen: Matemaattisia malleja 10 vuotta: Ei mallimonstereita vaan systeemiajattelua, Korkeakoulujen atk-uutiset, 3/94, ss. 16-17. Dimensio, 59, 2/95, ss. 6-8.

(IV:1)	H. Ehtamo: Tuuliselta pellolta suhisevaan lehvikköön, juhlapuhe Suomen itsenäisyyden 75-vuotisjuhlassa ja Köyliön yläasteen 25-vuotisjuhlassa 6.12.1992, Alasatakunta, 8.12.1992.