Talks in International Conferences and Workshops
- The replicator dynamics approach: democracy and corruption, EPCO 2021 - Portuguese Meeting on Optimal Control.
- Evolutionary information search dynamics against fake news, SING 16 - EUROPEAN MEETING ON GAME THEORY.
- An evolutionary dynamical approach: Democracy and corruption, CMMSE 2021.
- Cicles of corruption and democracy, ICDEA 2021.
- An evolutyonary dynamical approach: Democracy and corruption, 2nd Online International Conference on Nonlinear Dynamics and Complexity (NDC2021).
- Learning dynamics against fake news, EURO 2021, 31st European Conference on Operations Research, University of West Attica, Athens, Greece, 11-14 July, 2021.
- Dynamics of fake news, Research in Options 2020, Instituto Nacional de Matemática Pura e Aplicada IMPA, Rio de Janeiro, Brasil, November 29 – December 02, 2020 (online).
- Periodic Vaccination Strategic in Reinfection SIRI model, 11th Conference on Dynamical Systems Applied to Biology and Natural Sciences DSABNS 2020, Trento, Italy, February 4-7, 2020.
- Evolution of corruption in democratic states, Research in Options 2019, Instituto Nacional de Matemática Pura e Aplicada IMPA, Rio de Janeiro, Brasil, November 29 – December 1, 2019.
- Evolutionary dynamics of corruption and democracy, Workshop in Mathematical Economics, 15 November 2019, University of Porto.
- An evolutionary dynamical model for corruption cycles in democratic states, AMASES 2019 43rd Annual Meeting of the AMASES Association for Mathematics Applied to Social and Economic Sciences, Perugia, Italia, 9-11 September 2019
- Evolutionary dynamics of corruption in a democratic state, XX JOLATE Jornadas LatinoAmericanas de Teoría Económica, 5-6 August 2019, Baha Blanca, Argentina.
- A new approach to the reinfection threshold in epidemiology, ICIAM 2019 International Congress of Industrial and Applied Mathematics, 15-19 July 2019, Valencia, Spain.
- Evolutionary cycles of corruption in democratic countries, 19th SAET Conference on Current Trends in Economics, June 30th – July 6th, 2019 in Ischia, Italy
- Learning strategies in the Ignorant-Believer-Unbeliever rumor spreading model, VI Workshop on Computational Data Analysis and Numerical Methods (WCDANM), June 27-29, 2019, University of Beira Interior (UBI), Covilhã, Portugal
- Optimal strategies for international expansion with and without making dumping, EURO 2019 - 29th European Conference on Operational Research, 23-26 June 2019, Dublin, Ireland.
- An evolutionary dynamical model for corruption cycles in democratic states, Conference Internationale Dynamique, Jeux et Science, CIRM, Luminy, France, 3-7 June 2019.
- Piecewise chaotic attractors on the interval: topological and metric equivalence, PODE 2019 - Progress on Difference Equations, Instituto Politécnico de Bragança, Portugal, 27-30 May 2019.
- A Quantitative characterization of the reinfection threshold, 10th Workshop Dynamical Systems Applied to Biology and Natural Sciences DSABNS 2019, Napoli, Italia, February 3-6, 2019
- Implications of international trade agreements, Research in Options 2018 Honoring Bruno Dupire's 60th Birthday, Búzios, Rio de Janeiro, November
24 28, 2018. - Nash and social taris in welfare balanced trade agreements and externalities, I Congreso Iberoamericano de economía aplicada - ASEPELT,
"Turismo, Movilidad y Desarollo Sustenible", 14-17 November, 2018, Cartagena das Indias, Colombia. - How to avoid free-riding in touristic site preservation, I Congreso Iberoamericano de economía aplicada - ASEPELT, "Turismo, Movilidad y
Desarollo Sustenible", 14-17 November, 2018, Cartagena das Indias, Colombia. - Individual choices determining prices in oligopoly theory, UECE Game Theory Lisbon Meetings 2018, 25-27 October 2018, ISEG, Lisboa, Portugal.
- Vaccination traps, MCDF 2018 Dynamic models in Economics and Finance, University of Urbino, Italy, 6-8 September, 2018.
- A vaccination game, The Mathematics of Games in the Applied Sciences, 2018 International Congress of Mathematicians - Satellite Meeting, IME – UFF, Rio de Janeiro, August 09 – 11, 2018.
- Evolutionary vaccination dynamics, 11th European Conference on Mathematical and Theoretical Biology ECMTB, Universidade de Lisboa, Portugal 23-27 July 2018.
- Evolutionary vaccination dynamics, 2nd Portuguese Meeting in Biomathematics July 19–20, 2018, Universidade de Aveiro, Portugal.
- Evolutionary dynamics of corruption in a democratic state, European Conference on Iteration Theory, ECIT 2018, 3-6 July 2018, University of Murcia, Spain.
- Perfect Price Equilibrium and Social Influence on Choices, DGS VI-Jolate XIX, May 8-11, 2018, Universidad Nacional de Educación a Distancia (UNED), Madrid, Spain.
- Perfect equilibrium prices under social differentiation, UECE Game Theory Lisbon Meetings 2017, 9-11 November 2017, ISEG, Lisboa, Portugal.
- Strategic Decisions for Networks of Firms and Buyers, AMMCS 2017, 20-25 August, Waterloo, Ontario, Canada.
- Characterization of chaos for piecewise smooth maps, 23rd ICDEA, 24-28 July 2017, Timisoara, Romania.
- Game theory analysis in a rumour spreading model based on the SIR epidemic model, 17th International Conference Computational and Mathematical
Methods in Science and Engineering, July 4-8, 2017, Rota, Cádiz, Spain. - Evolutionary dynamics of vaccination games, BIOMATH 2017, 25-30 June 2017 Skukuza Camp, Kruger Park, South Africa.
- Prices in Competitive Markets, International Workshop on Mathematical Economics, 12-13 June 2017.
- Prices in Competitive Markets, Dynamics, Games and Science and Jornadas Latinoamericanas de Teoría Económica, DGS V - JOLATE XVIII, Escuela Superior de Economía, Instituto Politécnico Nacional, Ciudad de México, México, 22-26 May 2017.
- Explosion of smoothness for conjugacies, 6th IST-IME Meeting, in honour of Waldyr Oliva, Instituto Superior Técnico, Lisbon, Portugal, 5-9 September 2016.
- Local market structure in a Hotelling town, PET 16, Fundação Getúlio Vargas (FGV), Rio de Janeiro, Brasil, 11-13 July 2016.
- Hotelling Model in a network with uncertainty in costs of production, 16th SAET Conference on Current Trends in Economics, IMPA, Rio de Janeiro, Brasil, 6-9 July 2016.
- Impact of Nash and Social Equilibria in an International Trade Model, The 11th AIMS Conference on Dynamical Systems, Differential Equations and Applications,July 1 - July 5, 2016, Orlando, Florida, USA.
- Local Market Structure in a Hotelling Model, The 11th AIMS Conference on Dynamical Systems, Differential Equations and Applications,July 1 - July 5, 2016, Orlando, Florida, USA.
- Local Market Structure in a Hotelling Model, 2016 EPCO Portuguese Meeting on Optimal Control, Porto, Portugal, 20-21 June 2016.
- The Human Decisions, 4th International Conference on Dynamics, Games and Science: Decision models in a complex economy, 14-17 June 2016, UNED, Madrid, Spain.
- Dynamics of Human Decisions, The Dynamics of Complex Systems: A meeting in honour of the 60th birthday of Robert MacKay FRS, 18-20 May 2016, University of Warwick, England.
- A Dynamical Model of Immune Response by T Cells, Seventh Workshop Dynamical Systems Applied to Biology and Natural Sciences DSABNS 2016 Évora, Portugal, February 2-5, 2016
- Explosion of smoothness for conjugacies and equivalences, Geometric Aspects of Modern Dynamics, University of Porto Porto, Portugal, 11-15 January 2016.
- Price Dynamics in Hotelling Model, EURO 2015 - 27th European Conference on Operational Research, Glasgow, UK, 12-15 July 2015.
- Uncertainty costs on an international duopoly with tariffs, EURO 2015 - 27th European Conference on Operational Research, Glasgow, UK, 12-15 July 2015.
- A game theoretical decision model, The Cape Verde International Days on Mathematics 2015, University of Cape Verde, Campus of Mindelo, São Vicente, Cabo Verde, 27-30 April 2015.
- Stationary Sunspot Equilibrium as Limit of Expectation Coordination Failures. International Conference on Finance, Banking, and Regulation, Brasilia, Brazil (2014).
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Price competition in the Hotelling model with uncertainty on costs. Portuguese Meeting on Optimal Control 2014. University of Aveiro. Portugal (2014).
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A Linear Hoteling Town with Uncertainty. Dynamics Games and Optimisation. Warwick Mathematics Institute, University of Warwick, Coventry. UK (2014).
- Explosion of smoothness for equivalences between hyperbolic flows in 3-dimensional manifold, A Week on Dynamical Systems at UFRJ, Brazil (2013).
- As escolhas dos turistas, ICMC-USP, São Carlos, Brazil (2013).
- Resort Pricing and Bankruptcy, The 18th International Conference on Difference Equations and Applications (ICDEA2012), Barcelona, Spain, (2012).
- Dynamics of Human Decisions, International Conference on Game Theory, Stony Brook University, Stony Brook, USA, July (2012).
- On the convergence to Walrasian prices in random matching Edgewor- thian economies, International Conference on Game Theory, Stony Brook University, Stony Brook, USA, July (2012).
- Uncertainty effects in resort prices, The 9th AIMS Conference on Dynam- ical Systems, Differential Equations and Applications Orlando, Florida, USA, July (2012).
- Tilings for Anosov diffeomorphisms. Plenary Talk, International Work- shop on Nonlinear Maps and their Applications, University of Évora, Por- tugal (2011).
- Bayesian-Nash equilibria in theory of planned behavior. The 3nd Annual UECE - Lisbon Meetings - Game Theory and Applications ISEG, Tech- nical University of Lisbon, Portugal (2011).
- Tilings and Bussola for Making Decisions. The 3nd Annual UECE - Lisbon Meetings - Game Theory and Applications ISEG, Technical University of Lisbon, Portugal (2011).
- Tilings on the real line and Anosov diffeomorphisms. Plenary Talk, Work- shop on Dynamical Systems, UFBA, Bahia, Salvador, Brasil (2011).
- A influência dos grupos no sucesso escolar dos estudantes. Invited Talk, 4º Workshop do Projeto Klein em Língua Portuguesa, IM-UFG, Goiânia, Brasil (2011).
- On the Convergence to Walrasian Prices in Random Matching Edgewor- thian Economies. 11th SAET Conference, Faro, Portugal (2011).
- A Hotelling-Type Network. 11th SAET Conference, Faro, Portugal (2011).
- Renormalization gives all surface Anosov diffeomorphisms with a smooth invariant measure. 17th International Conference on Difference Equations and Applications (ICDEA 2011), Université du Québec, Trois-Rivières, Canada (2011).
- A Dynamical Model for Tregs and Conventional T Cells. Invited Talk, 7th International Congress on Industrial and Applied Mathematics (ICIAM 2011), Vancouver, Canada (2011).
- Epidemiological Thresholds. Invited Talk, 7th International Congress on Industrial and Applied Mathematics (ICIAM 2011), Vancouver, Canada (2011).
- Resort Prices and Bankruptcy. Invited Talk, 7th International Congress on Industrial and Applied Mathematics (ICIAM 2011), Vancouver, Canada (2011).
- Leaders Influence in Individuals Decisions. Invited Talk, 7th International Congress on Industrial and Applied Mathematics (ICIAM 2011), Vancouver, Canada (2011).
- Game Theoretical Model in Theory of Planned Behavior. Invited Talk, 7th International Congress on Industrial and Applied Mathematics (ICIAM 2011), Vancouver, Canada (2011).
- Universality in Energy Sources. Invited Talk, 7th International Congress on Industrial and Applied Mathematics (ICIAM 2011), Vancouver, Canada (2011).
- Networks a la Hotelling and Incomplete Information. Invited Talk, 7th International Congress on Industrial and Applied Mathematics (ICIAM 2011), Vancouver, Canada (2011).
- Imunological Thresholds. Invited Talk, 7th International Congress on Industrial and Applied Mathematics (ICIAM 2011), Vancouver, Canada (2011).
- Tilings and Bussola for Making Decisions. Invited Talk, 7th International Congress on Industrial and Applied Mathematics (ICIAM 2011), Vancou- ver, Canada (2011).
- A Hotelling-Type Network. Public Economic Theory Conference 2011 (PET11), Indiana University, Bloomington, USA (2011).
- Renormalizing the pendulum after Galileo’s observation. Plenary Talk, Workshop Internacional de Sistemas Dinâmicos. Celebrando os 90 anos do Professor Mauricio Peixoto, IMPA, Rio de Janeiro, Brazil (2011).
- Piecewise R&D Dynamics on costs. XXXII Congreso Nacional de Es- tadśtica e Investigación Operativa, Universidade da Conuña, Spain (2010).
- A Hotelling-type network (in the place of Telmo Parreira), XXXII Con- greso Nacional de Estadśtica e Investigación Operativa, Universidade da Conuña, Spain (2010).
- An economical model for dumping (in the place of José Martins), XXXII Congreso Nacional de Estadística e Investigación Operativa, Universidade da Conuña, Spain (2010).
- Modelling human decisions with game theory (in the place of Helena Ferreira), International Congress of Mathematicians, Hyderabad, India (2010).
- R & D dynamics on costs (in the place of Miguel Ferreira), International
- Congress of Mathematicians, Hyderabad, India (2010).
- Hotelling model with uncertainty on the production cost and networks, International Congress of Mathematicians, Hyderabad, India (2010).
- Universality in the financial market,International Congress of Mathemati- cians, Hyderabad, India (2010).
- Immune response dynamics by T cells (in the place of Bruno Oliveira), International Congress of Mathematicians, Hyderabad, India (2010).
- Golden tilings (in the place of João Almeida), International Congress of Mathematicians, Hyderabad, India (2010).
- Hotelling model with uncertainty on the production cost and Networks, ICM Satellite Conference on Probability and Stochastic Processes, Ban- galore, India (2010).
- Dynamic Thresholds in Biology, 24th European Conference on Operational Research, Lisbon, Portugal (2010).
- Modelling Human Behavior (in the place of PhD student Helena Fer- reira), 24th European Conference on Operational Research, Lisbon, Por- tugal (2010).
- Tilings and Bussola for Making Decisions, International Conference on Modeling, Optimization and Dynamics, Porto, Portugal (2010).
- Universality in stock exchange market, X Jornadas Latino Americanas de Teoria Económica, Bahia Blanca, Argentina (2009).
- Patents in New Technologies, European Conference on Complex Systems 2009, University of Warwick, UK (2009).
- Universalidade das flutuações nas manchas solares e no Dow Jones, Ciência 2009, meeting promoted by Laboratórios Associados with the support of Fundação para a Ciência e a Tecnologia, Lisbon, Portugal (2009).
- Dynamical Systems and Game Theory, 23rd European Conference on Operational Research, Bonn, Germany (2009).
- A game theoretical model of planned behavior (in the place of PhD student Helena Ferreira), 23rd European Conference on Operational Research, Bonn, Germany (2009).
- Patents in new technologies, Progress on Difference Equations, Poland (2009).
- Bayesian-Nash Equilibria in the Theory of Planned Action, Workshop in Game Theory, Braga, Portugal (2008).
- Signalling to the home policymaker, LAMES2008 Latin American Meeting of the Econometric Society, Rio de Janeiro, Brazil (2008).
- Bayesian-Nash Equilibria in the Theory of Planned Action, LAMES2008 Latin American Meeting of the Econometric Society, Rio de Janeiro, Brazil (2008).
- Fine Structures of Hyperbolic Diffeomorphisms, DYNA2008 in honor of Mauricio Peixoto and David Rand, Braga, Portugal (2008).
- Bayesian-Nash Equilibria in the Theory of Planned Action, DYNA2008 in honor of Mauricio Peixoto and David Rand, Braga, Portugal (2008).
- Reciprocal dumping under antidumping enforcement and uncertain tech- nology. XXIII Jornadas de Economia Industrial. Reus, Spain (2008).
- R&D and cost dynamics. Palestine Conference in Modern Trends in Math- ematical and Physics. Birzeit, Palestine (2008).
- Eigenvalues. Palestine Conference in Modern Trends in Mathematical and Physics. Birzeit, Palestine (2008).
- Behavioural and dynamical scenarios for contingent claims valuation in incomplete markets. The 2008 Australasian Meeting of the Econometric Society. Wellington, New Zealand (2008).
- The higher moments dynamic on SIS model. ECMTB08 - European Con- ference on Mathematical and Theoretical Biology. Edinburgh, Scotland (2008).
- Antidumping policies for differentiated good with uncertain production costs. VIII Congreso Galego de Estatística e Investigación de Opearcións. Santiago de Compostela, Spain (2007).
- Signalling strategies of trade policies. Econophysics Colloquium and be- yond. Ancona, Italy (2007).
- The analytic expressions of the phase transition lines of the spatial stochas- tic epidemic model SIRI in the pair approximation scheme, Mathematical Methods and Modeling of Biophysical Phenomena, Búzios, Brazil (2007).
- Hyperbolic dynamics, The Twelfth International Conference on Differ- ence Equations and Applications (ICDEA07), dedicated to the Memory of Sousa Ramos, Portugal (2007).
- Optimal investments in repeated Cournot competition. 6th International Congress on Industrial and Applied Mathematics, ICIAM 07. Zurich, Switzerland (2007).
- Pricing in incomplete markets. 22nd European Conference on Operational Research, EURO XXII. Prague, Check Republic (2007).
- R&D investments with spillovers. Optimization 2007. Porto, Portugal (2007).
- Geometric measures for hyperbolic diffeomorphisms. International Con- ference: Progress on Difference Equations, Salzburg, Austria (2007).
- Long term effects of small perturbations in a dynamic duopoly. 2006 South and South East Asia Econometric Society Meeting, SAMES06, Chennai, India (2006).
- A modified model of an Edgeworthian Economy. 2006 South and South East Asia Econometric Society Meeting, SAMES06, Chennai, India (2006).
- The effect of a Prisoner’s Dilemma in an Edgeworthian. VII JOLATE Jornadas Latino-americanas de Teoria Económica joint with Workshop on Mathematical Economics, celebrating the 60th anniversary of Aloisio Araújo. IMPA, Rio de Janeiro, Brazil (2006).
- Investment dynamics in the reduction of production costs. VII JOLATE Jornadas Latino-americanas de Teoria Económica joint with Workshop on Mathematical Economics, celebrating the 60th anniversary of Aloisio Araújo. IMPA, Rio de Janeiro, Brazil (2006).
- Smooth conjugacies and Eigenvalues. International Conference Celebrat- ing Welington 60th birthday. Salvador, Brazil (2006).
- A Model of Local Immune Responses by T cells. Dynamics Days Europe 2006. Crete, Greece (2006).
- Optimal investments in the reduction of production costs. International Conference on Interdisciplinary Mathematical & Statistical Techniques. Polytechnic Institute of Tomar, Portugal (2006).
- Pseudo-Anosov diffeomorphisms in new smooth structures. International Congress of Mathematicians ICM 2006. Madrid, Spain (2006).
- Dynamics of R&D investment strategies in Cournot competitions. Inter- national Congress of Mathematicians ICM 2006. Madrid, Spain (2006).
- Dynamics of R&D investment strategies in duopoly competitions. 17th International Conference on Game Theory. Stony Brook, NY, USA (2006).
- Optimal investments in the reduction of production costs. 21st European Conference on Operational Research. Reykjavik, Iceland (2006).
- R&D programs in a duopoly competition. First Galaico Duriense, one day meeting in Game Theory. Porto, Portugal (2006).
- Dinâmica de estratégias de investimento em competições do tipo Cournot. National Meeting of the Portuguese Mathematical Society. (Substituted by Flávio Ferreira). Lisbon, Portugal (2006).
- Repeated Cournot competition: Nash investment equilibrium to increase the demand. Spain, Italy, The Netherlands Meeting on Game Theory. Foggia, Italy (2006).
- R&D investment strategies with uncertainty. International Congress on Mathematics. Paphos, Cyprus (2006).
- Dynamics in a duopoly model with R&D investments. International Con- ference on Knowledge Engineering and Decision Support. Lisbon, Portugal (2006).
- Cournot model: repeated R&D investments for non-identical firms. Math- ematical Methods in Engineering. Ankara, Turkey (2006).
- New pseudo-smooth structures on paper surfaces and Mañé-Bochi duality. School and Workshop on Dynamical Systems. IMPA, Rio de Janeiro, Brazil (2006).
- The Bayesian Nash equilibrium on a stochastic Stackelberg duopoly. Work- shop Nonlinear Economic Dynamics. Faculty of Economics, Palazzo Bat- tiferri, University of Urbino. Italy (2005).
- Mini-curso: Teoria dos Jogos com aplicações à Economia e à Biologia. SPM meeting, Polythecnic Institute of Porto, Portugal (2004).
- Dinâmica hiperbólica em superfícies. Workshop in Dynamical Systems, University of Maceo, Brazil (2004).
- Geometric measures for hyperbolic diffeomorphisms with basic sets on sur- faces. International Workshop on Robustness and Partial Hyperbolicity. Buzios, Brazil (2003).
- Geometric measures for hyperbolic diffeomorphisms with basic sets on surfaces. Symbolic Dynamics and Ergodic Theory: Geometric and Prob- abilistic Aspects of Dynamical Systems. Symposium year at University of Warwick (2003).
- Cross ratios versus smoothness. Workshop on Real and Complex One- dimensional Holomorphic Dynamics. University of Warwick, UK (2002).
- New smooth structures for uniformly hyperbolic pseudo-Anosov maps. New Directions in Dynamical Systems. University of Kyoto, Japan (2002).
- Geometric measures for hyperbolic diffeomorphisms on surfaces. International Congress of Mathematicians, ICM2002. Beijing, China (2002).
- The hyperbolicity of the renormalization operator in C 3 . Workshop on Dynamical Systems. ICTP-International Centre for Theoretical Physics, Trieste, Italy (2001).
- Non-existence of affine Plykin attractors. Progress in Nonlinear Science, International Conference Dedicated to the Anniversary of Alexander A. Andronov. University of Nizhny Novgorod, Russia (2001).
- The solenoid and the circle. Mathematics and Theoretical Physics; A Conference to Celebrate Dennis Sullivan’s 60th Birthday. SUNY State University of New York, Stony Brook, USA (2001).
- Geometric measures for hyperbolic diffeomorphisms. Recent Trends in Dynamics II. University of Porto, Portugal (2001).
- Geometric measures for hyperbolic surfaces dynamics. International Con- ference on Dynamical Systems, dedicated to the 60th anniversary of Prof. Jacob Palis. IMPA, Rio de Janeiro, Brazil (2000).
- Global hyperbolicity of renormalization operator for C 3 unimodal map- pings. Workshop in Dynamical Systems. International Centre for Mathema- tical Sciences, Edinburgh, Scotland (2000).
- Flexibility and rigidity in hyperbolic dynamics. Conference on Differen- tial Equations and Dynamical Systems, in honour of Waldyr Oliva. IST, Technical University of Lisbon, Portugal (2000).
- Hyperbolic of renormalization for C 3 unimodal maps. Workshop in Holo- morphic Dynamics, Conformal and Invariant Measures. Stefan Banach International Mathematical Centre, Warsaw, Poland (1999).
- Rigidity and flexibility for hyperbolic dynamics. Workshop in Holomor- phic Dynamics, Conformal and Invariant Measures. Stefan Banach Inter- national Mathematical Centre, Warsaw, Poland (1999).
- Rigidity and flexibility. International Conference of Mathematics ICM 1998. Berlim, Alemanha (1998).
- Renormalization gives all surfaces Anosov diffeomorphisms with a smooth invariant measure. 4th Quadriennal International Conference on Dynam- ical Systems. IMPA, Rio de Janeiro, Brazil (1997).
- Rotações e aplicações de Anosov. 6º Encontro da Sociedade Portuguesa de Matemática. IST, Technical University of Lisbon, Portugal (1996).
- The moduli space of smooth conjugacy classes of expanding maps in one dimension. Workshop in Finite Dimensional Dynamics. Newton Institute, Cambridge, UK (1995).
- Renormalization and the moduli space for diffeomorphisms of the circle.
- Conference in Finite and Infinite Dimensional Dynamical Systems. Newton Institute, Cambridge, UK (1995).
- Markov maps on train tracks. Nato ASI. Hillerod, Denmark (1993).
- Renormalization theory (Video). Graduate Centre, City University of New York, USA. (1992).
- Markov families, renormalization and Feigenbaum universality. Workshop on Renormalization of Dynamical Systems. University of Warwick, UK (1992).
- Aplicações de teoria de singularidades em problemas de controle. Mini- curso de pós-graduação, University of Porto, Portugal (1988).