Publications by year

Chen, X, Gómez-Rodríguez, C. & Ferrer-i-Cancho, R. (2017). A dependency look at the reality of constituency.
[ e-print ]

Ferrer-i-Cancho, R. (2017). The placement of the head that maximizes predictability. An information theoretic approach. Glottometrics 39, 38-71.
[ e-print ]

Ferrer-i-Cancho, R. & Vitevitch, M. S. (2017). The origins of Zipf's meaning-frequency law.
[ e-print ] 

Ferrer-i-Cancho, R., Gómez-Rodríguez, C. & Esteban, J. L. (2017). Are crossing dependencies really scarce?
[ e-print ]
Casas, B., Hernández-Fernández, A., Català, N., Ferrer-i-Cancho, R. & Baixeries, J. (2017). Polysemy and brevity versus frequency in speech transcripts.

Casas, B., Català, N., Ferrer-i-Cancho, R., Hernández-Fernández, A. & Baixeries, J. (2016). The polysemy of the words that children learn over time.
[ e-print ]

Ferrer-i-Cancho, R. (2017). Optimization models of natural communication. Journal of Quantitative Linguistics, in press.
[ doi: 10.1080/09296174.2017.1366095 ]

Ferrer-i-Cancho, R. (2017). Towards a theory of word order. Comment on "Dependency distance: a new perspective on syntactic patterns in natural language" by Haitao Liu et al. Physics of Life Reviews 21, 218-220.
[ doi: 10.1016/j.plrev.2017.06.019 ]

Bentz, C., Alikaniotis, D., Cysouw, M. & Ferrer-i-Cancho, R. (2017). The entropy of words – learnability and expressivity across more than 1000 languages. Entropy 19(6), 275. 
[ doi:10.3390/e19060275 ]

Ferrer-i-Cancho, R. (2017). A commentary on “The now-or-never bottleneck: a fundamental constraint on language”, by Christiansen and Chater (2016). Glottometrics 38, 107-111.
[ e-print ]

Ferrer-i-Cancho, R. (2017). Random crossings in dependency trees. Glottometrics 37, 1-12.
[ e-print ]

Elvevåg, B., Foltz, P. , Rosenstein, M., Ferrer-i-Cancho, R., De Deyne, S., Mizraji, E. & Cohen, A. (2017). Thoughts about disordered thinking: measuring and quantifying the laws of order and disorder. Schizophrenia Bulletin 43 (3), 509–513.
[ doi: 10.1093/schbul/sbx040 ]

Esteban, J. L. & R. Ferrer-i-Cancho, R. (2017). A correction on Shiloach's algorithm for minimum linear arrangement of trees. SIAM Journal of Computing 46(3), 1146-1151.
doi: 10.1137/15M1046289 ]

Ferrer-i-Cancho, R. (2017). The optimality of attaching unlinked labels to unlinked meanings. Glottometrics 36, 1-16.
[ e-print ]

Esteban, J. L., Ferrer-i-Cancho, R., & Gómez-Rodríguez, C. (2016). The scaling of the minimum sum of edge lengths in uniformly random trees. Journal of Statistical Mechanics, 063401.
[ doi: 10.1088/1742-5468/2016/06/063401 ]

Ferrer-i-Cancho, R. (2016). The meaning-frequency law in Zipfian optimization models of communication. Glottometrics 35, 28-37.
[ e-print ]

Ferrer-i-Cancho, R. (2016). Compression and the origins of Zipf's law for word frequencies. Complexity 21 (S2), 409-411.
[ doi: 10.1002/cplx.21820 ]

Ferrer-i-Cancho, R. & Gómez-Rodríguez, C. (2016). Crossings as a side effect of dependency lengths. Complexity 21 (S2), 320-328.
[ doi: 10.1002/cplx.21810 ]

Hernández-Fernández, A., Casas, B., Ferrer-i-Cancho, R. & Baixeries, J. (2016). Testing the robustness of laws of polysemy and brevity versus frequency. 4th International Conference on Statistical Language and Speech Processing (SLSP 2016). P. Král and C. Martín-Vide (eds.). Lecture Notes in Computer Science 9918, pp. 19–29.
[ doi: 10.1007/978-3-319-45925-7_2  ]

Gómez-Rodríguez, C. & Ferrer-i-Cancho, R. (2016). The scarcity of crossing dependencies: a direct outcome of a specific constraint?
[ e-print ]

Ferrer-i-Cancho, R., Lusseau, D. & McCowan, B. (2016). Parallels of human language in the behavior of bottlenose dolphins.
[ e-print ]

Ferrer-i-Cancho R. (2016). Kauffman's adjacent possible in word order evolution. In S.G. Roberts, C. Cuskley, L. McCrohon, L. Barceló-Coblijn, O. Feher & T. Verhoef (eds.). The Evolution of Language: Proceedings of the 11th International Conference (EVOLANG11). New Orleans, USA, March 21-24.
[ e-print ]

Ferrer-i-Cancho, R. (2016). Non-crossing dependencies: least effort, not grammar. In: Towards a theoretical framework for analyzing complex linguistic networks, Mehler, A., Lücking, A., Banisch, S., Blanchard, P. & Job, B. (eds.). Springer (Berlin), pp. 203-234. 
[ doi: 10.1007/978-3-662-47238-5_10 ]

Ferrer-i-Cancho, R. & Gómez-Rodríguez, C. (2016). Liberating language research from dogmas of the 20th century. Glottometrics 33, 33-34.
[ e-print ]
See also
Gustison, M.L, Semple, S., Ferrer-i-Cancho, R. & Bergman, T. J.  (2016). Gelada vocal sequences follow Menzerath’s linguistic law.  Proceedings of the National Academy of Sciences USA 113 (19), E2750-E2758.
[ cover, doi: 10.1073/pnas.1522072113 ]

Hernández-Fernández, A. & Ferrer-i-Cancho, R. (2016). The infochemical core. Journal of Quantitative Linguistics 23 (2), 133-153.
[ doi: 10.1080/09296174.2016.1142323 ]

Kershenbaum, A., Blumstein, D. T. & Roch, M. A. et al (2016). Acoustic sequences in non-human animals: A tutorial review and prospectus. Biological Reviews 91 (1), 13–52.
[ doi: 10.1111/brv.12160 ]

Lozano, A., Casas, B., Bentz, C. & Ferrer-i-Cancho, R. (2016). Fast calculation of entropy with Zhang's estimator. In: Issues in Quantitative Linguistics 4. Dedicated to Reinhard Köhler on the occasion of his 65th birthday. E. Kelih, R. Knight, J. Macutek and A. Wilson (eds.). No. 23 of the series “Studies in Quantitative Linguistics”. Lüdenscheid: RAM-Verlag. pp. 273-285.
[ e-print ]

Bentz, C. & Ferrer-i-Cancho, R. (2015). Zipf's law of abbreviation as a language universal. Capturing Phylogenetic Algorithms for Linguistics. Lorentz Center Workshop, Leiden, October 2015
[ e-print ]

Ferrer-i-Cancho, R., Bentz, C. & Seguin, C. (2015). Compression and the origins of Zipf's law of abbreviation.
[ e-print ]

Semple, S., Ferrer-i-Cancho, R., Bergman, T., Hsu, M., Agoramoorthy, G. & Gustison, M. (2015). Linguistic laws in primate vocal communication. Proceedings of the 6th European Federation for Primatology Meeting, XXII Italian Association of Primatology Congress Rome, Italy, August 25-28.
Folia Primatologica 86, 357.
[ doi: 10.1159/000435825 ]

Corral, A., Boleda, G. & Ferrer-i-Cancho, R. (2015). Zipf's law for word frequencies: word forms versus lemmas in long texts. PLoS ONE 10 (7), e0129031.
[ doi: 10.1371/journal.pone.0129031 ]

Ferrer-i-Cancho, R. (2015). The placement of the head that minimizes online memory. A complex systems approach. Language Dynamics and Change 5 (1), 114-137.
[ doi: 10.1163/22105832-00501007 ]

Ferrer-i-Cancho, R. (2015). Reply to the commentary "Be careful when assuming the obvious", by P. Alday. Language Dynamics and Change 5 (1), 147-155.
[ doi: 10.1163/22105832-00501009 ]
This article is a reply to

Alday, P. (2015). Be careful when assuming the obvious. Commentary on "The placement of the head that minimizes online memory: a complex systems approach". Language Dynamics and Change 5 (1), 138-146.
[ doi: 10.1163/22105832-00501008 ]
Castela, S., Baixeries, J., Garrard, P., Elvevåg, B. & Ferrer-i-Cancho, R. (2014). Milestones in the scaling of block entropy.

Ferrer-i-Cancho, R. (2014). A stronger null hypothesis for crossing dependencies. Europhysics Letters 108 (5), 58003.
[ doi: 10.1209/0295-5075/108/58003 ]
Editor's choice

Editor's Choice Articles 2014
Ferrer-i-Cancho, R., Hernández-Fernández, A., Baixeries, J., Dębowski, Ł. & Macutek, J. (2014). When is Menzerath-Altmann law mathematically trivial? A new approach. Statistical Applications in Genetics and Molecular Biology 13 (6), 633–644.
[ doi: 10.1515/sagmb-2013-0034 ]

Ferrer-i-Cancho, R. (2014). Beyond description. Comment on "Approaching human language with complex networks" by Cong &  Liu. Physics of Life Reviews 11 (4), 621–623.
[ doi: 10.1016/j.plrev.2014.07.014 ]

Ferrer-i-Cancho, R. & Liu, H. (2014). The risks of mixing dependency lengths from sequences of different length. Glottotheory 5 (2), 143-155.
[ doi: 10.1515/glot-2014-0014 ]

Ferrer-i-Cancho, R. (2014). What if we are not at the center? In: THE EVOLUTION OF LANGUAGE - Proceedings of the 10th International Conference (EVOLANG10), Cartmill, E. A., Roberts, S., Lyn, H. & Cornish, H. (eds.). Evolution of Language Conference (Evolang 2014). Vienna, Austria, April 14-17. p. 11
[ PDF ]

Ferrer-i-Cancho, R. (2014). Why might SOV be initially preferred and then lost or recovered? A theoretical framework. In: THE EVOLUTION OF LANGUAGE - Proceedings of the 10th International Conference (EVOLANG10), Cartmill, E. A., Roberts, S., Lyn, H. & Cornish, H. (eds.). Evolution of Language Conference (Evolang 2014). Vienna, Austria, April 14-17. pp. 66-73.
[ doi: 10.1142/9789814603638_0007 ]

Casas, B., Català, N., Ferrer-i-Cancho, R. & Baixeries, J. (2014). The evolution of polysemy in child language. In: THE EVOLUTION OF LANGUAGE - Proceedings of the 10th International Conference (EVOLANG10), Cartmill, E. A., Roberts, S., Lyn, H. & Cornish, H. (eds.). Evolution of Language Conference (Evolang 2014). Vienna, Austria, April 14-17. pp. 409-410.
[ doi: 10.1142/9789814603638_0068 ]

Ferrer-i-Cancho, R., Dębowski, Ł. & Moscoso del Prado Martín, F. (2013). Constant conditional entropy and related hypotheses. Journal of Statistical Mechanics, L07001.
[ doi: 10.1088/1742-5468/2013/07/L07001 ]

Baronchelli, A., Ferrer-i-Cancho, R., Pastor-Satorras, R., Chater, N. & Christiansen, M. H. (2013). Networks in cognitive science. Trends in Cognitive Sciences 17, 348-360.
[ doi: 10.1016/j.tics.2013.04.010 ]

Ferrer-i-Cancho, R., Hernández-Fernández, A., Lusseau, D., Agoramoorthy, G., Hsu, M. J. & Semple, S. (2013). Compression as a universal principle of animal behavior. Cognitive Science 37 (8), 1565–1578.
[ doi: 10.1111/cogs.12061, e-print ]

Semple, S., Hsu, M. J., Agoramoorthy, G., Ferrer-i-Cancho, R. (2013). The law of brevity in macaque vocal communication is not an artifact of analyzing mean call durations. Journal of Quantitative Linguistics, 20 (3), 209-217.
[ doi: 10.1080/09296174.2013.799917 ]

Ferrer-i-Cancho, R. (2013). Hubiness, length, crossings and their relationships in dependency trees. Glottometrics 25, 1-21.
[ e-print ]

Ferrer-i-Cancho, R. & Hernández-Fernández, A. (2013). The failure of the law of brevity in two New World primates. Statistical caveats. Glottotheory 4 (1), 45-55.
[ doi: 10.1524/glot.2013.0004 ]

Ferrer-i-Cancho, R., Baixeries, J. & Hernández-Fernández, A. (2013). Erratum to "Random models of Menzerath-Altmann law in genomes" (BioSystems 107 (3), 167–173). BioSystems 111 (3), 216-217.
[ doi: 10.1016/j.biosystems.2013.01.004 ]

Baixeries, J., Elvevåg, B. & Ferrer-i-Cancho, R. (2013). The evolution of the exponent of Zipf's law in language ontogeny. PLoS ONE 8 (3), e53227.
[ doi: 10.1371/journal.pone.0053227 ]

Ferrer-i-Cancho, R., Forns, N., Hernández-Fernández, A., Bel-Enguix, G. & Baixeries, J. (2013). The challenges of statistical patterns of language: the case of Menzerath’s law in genomes. Complexity 18 (3), 11–17.
[ doi: 10.1002/cplx.21429 ]

This article reviews mathematical, statistical and conceptual flaws of

Solé, R. V.  (2010). Genome size, self-organization and DNA's dark matter.  Complexity 16 (1), 20-23.
[ doi: 10.1002/cplx.20326 ]

R. V. Solé's reactions in a popular science blog (in Spanish)

Baixeries, J., Hernández-Fernández, A., Forns, N. & Ferrer-i-Cancho, R. (2013). The parameters of Menzerath-Altmann law in genomes. Journal of Quantitative Linguistics 20 (2), 94–104.
[ doi: 10.1080/09296174.2013.773141 ]

Baixeries, J., Ferrer-i-Cancho, R., Elvevåg, B. (2012). The exponent of Zipf’s law in language ontogeny. Evolution of Language Conference (Evolang 2012). Kyoto, Japan, March 13-16. In: THE EVOLUTION OF LANGUAGE - Proceedings of the 9th International Conference (EVOLANG9), J, Scott-Phillips, T, Tamariz, M, Cartmill, E, Hurford (eds.), World Scientific, Singapore, pp. 409-410.
[ doi:  10.1142/9789814401500_0055 ]

Ferrer-i-Cancho, R. & McCowan, B. (2012). The span of correlations in dolphin whistle sequences. Journal of Statistical Mechanics, P06002.
[ doi: 10.1088/1742-5468/2012/06/P06002 ]

Baixeries, J., Hernández-Fernández, A. & Ferrer-i-Cancho, R. (2012). Random models of Menzerath-Altmann law in genomes.  BioSystems 107 (3), 167–173.
[ doi: 10.1016/j.biosystems.2011.11.010 ]

Ferrer-i-Cancho, R. & Moscoso del Prado Martín, F. (2011). Information content versus word length in random typing. Journal of Statistical Mechanics, L12002.
[ doi: 10.1088/1742-5468/2011/12/L12002 ]

Hernández-Fernández, A., Baixeries, J., Forns, N. & Ferrer-i-Cancho, R. (2011). Size of the whole versus number of parts in genomes. Entropy 13 (8), 1465-1480.
[ doi: 10.3390/e13081465 ]


Ferrer i Cancho, R. (2010). Information theory. In: The Cambridge encyclopedia of the language sciences, Colm Hogan, P. (ed.). Cambridge University Press. pp. 389. ISBN: 9780521866897
[ preprint ]

Ferrer i Cancho, R. (2010). Network theory. In: The Cambridge encyclopedia of the language sciences, Colm Hogan, P. (ed.). Cambridge University Press. pp. 555-557. ISBN: 9780521866897
[ preprint ]

Kello, C. T., Brown, G. D. A., Ferrer-i-Cancho, R., Holden, G., Linkenkaer-Hansen, K., Rhodes, T. & Van Orden, G. C. (2010). Scaling laws in cognitive sciences. Trends in Cognitive Sciences 14 (5), 223-232.
[ doi: 10.1016/j.tics.2010.02.005 ]

"Corpo e pensiero. L' attività è scandita da regole matematiche", by  Massimo Piattelli-Palmarini (PDF) on the Italian newspaper Il Corriere della Sera.

Ferrer-i-Cancho, R. & Elvevåg, B. (2010). Random texts do not exhibit the real Zipf's law-like rank distribution. PLoS ONE 5 (3), e9411.
[ doi: 10.1371/journal.pone.0009411 ]

Random Character Sequences Do Not Follow Zipf's Law.  A demonstration for Mathematica by Osman Tuna Gökgöz

Ferrer-i-Cancho, R. & Forns, N. (2009). The self-organization of genomes. Complexity 15 (5), 34-36.
doi: 10.1002/cplx.20296 ]

Reviewed in

Solé, R. V.  (2010). Genome size, self-organization and DNA's dark matter.  Complexity 16 (1), 20-23.
[ doi: 10.1002/cplx.20326  ]

Ferrer-i-Cancho, R. & McCowan, B. (2009). A law of word meaning in dolphin whistle types. Entropy 11 (4), 688-701.
[ doi: 10.3390/e11040688 ]

Ferrer-i-Cancho, R. & Lusseau, D. (2009). Efficient coding in dolphin surface behavioral patterns. Complexity 14 (5), 23-25.
[ doi: 10.1002/cplx.20266 ]

Channel 4 news (UK), 3 Agust 2009
Onda Regional de Murcia (programa Adelantos), 31 de julio de 2009


Ferrer-i-Cancho, R. & Gavaldà, R. (2009). The frequency spectrum of finite samples from the intermittent silence process. Journal of the American Society for Information Science and Technology 60 (4), 837-843.
[ doi: 10.1002/asi.21033 ]

Ferrer-i-Cancho, R. (2008). Some word order biases from limited brain resources. A mathematical approach. Advances in Complex Systems 11 (3), 394-414.
[ doi: 10.1142/S0219525908001702 ]

Ferrer-i-Cancho, R. (2008). Some limits of standard linguistic typology. The case of Cysouw's models for the frequencies of the six possible orderings of S, V and O. Advances in Complex Systems 11 (3), 421-432.
[ doi: 10.1142/S0219525908001726 ]

This article is a reply to

Cysouw, M. (2008). Linear order as a predictor of word order regularities. A reply to Ferrer-i-Cancho (2008). Advances in Complex Systems 11 (3):415-420.
[ doi: 10.1142/S0219525908001714 ]

Smith, A. D. M., Smith, K., & Ferrer i Cancho, R. (2008). The Evolution of Language: Proceedings of the 7th International Conference (EVOLANG7). Singapore: World Scientific Press. From

Ferrer i Cancho, R., Lorenzo, G. & Longa, V. (2008). Long-distance dependencies are not uniquely human. In: The Evolution of Language: Proceedings of the 7th International Conference (EVOLANG7). Smith, A. D. M., Smith, K. & Ferrer i Cancho, R (eds.). Singapore: World Scientific Press, pp. 115-122.
[ e-print ]

Ferrer i Cancho, R. & Hernández Fernández, A. (2008). Power laws and the golden number. In: “Problems of general, germanic and slavic linguistics”, Altmann, G., Zadorozhna, I. & Matskulyak, Y. (eds.), Chernivtsi: Books - XXI. pp. 518-523.
[ preprint ]

Ferrer i Cancho, R. & Díaz-Guilera, A. (2007). The global minima of the communicative energy of natural communication systems. Journal of Statistical Mechanics, P06009.
[ doi: 10.1088/1742-5468/2007/06/P06009 ]

Ferrer i Cancho, R., Mehler, A., Pustylnikov, O. & Diaz-Guilera (2007). Correlations in the organization of large-scale syntactic dependency networks, In: TextGraphs-2: Graph-Based Algorithms for Natural Language. Association for Computational Linguistics, Rochester, NY, USA, pp. 65-72.
[ ACL Anthology ]

Ferrer i Cancho, R., Capocci, A. & Caldarelli, G. (2007). Spectral methods cluster words of the same class in a syntactic dependency network. International Journal of Bifurcation and Chaos 17 (7), 2453 - 2463.
[ doi: 10.1142/S021812740701852X ]

Ferrer i Cancho, R. (2006). Why do syntactic links not cross? Europhysics Letters 76 1228-1235.
[ doi: 10.1209/epl/i2006-10406-0]

Ferrer i Cancho, R. & Lusseau, D. (2006). Long-term correlations in the surface behavior of dolphins. Europhysics Letters 74, 1095-1101.
[ doi: 10.1209/epl/i2005-10596-9 ]

Ferrer i Cancho, R. (2006). On the universality of Zipf's law for word frequencies. In: "Exact methods in the study of language and text. In honor of Gabriel Altmann", Grzybek, P. & Köhler,R. (eds.) 131-140. Berlin: Gruyter.
[ google books ]

Ferrer i Cancho, R. (2006). When language breaks into pieces. A conflict between communication through isolated signals and language. BioSystems 84, 242-253.
[ doi: 10.1016/j.biosystems.2005.12.001 ]

Ferrer i Cancho, R. (2005). The structure of syntactic dependency networks: insights from recent advances in network theory. In: "The problems of quantitative linguistics", Altmann, G., Levickij, V. & Perebyinis, V. (eds.). Chernivtsi: Ruta. pp. 60-75.
[ PDF ]

Ferrer i Cancho, R. (2005). Hidden communication aspects in the exponent of Zipf's law. Glottometrics 11, 99-119.

Ferrer i Cancho, R. (2005). Zipf's law from a communicative phase transition. European Physical Journal B 47, 449-457.
[ doi: 10.1140/epjb/e2005-00340-y ]

Ferrer i Cancho, R. & Servedio, V.D.P. (2005). Can simple models explain Zipf's law in all cases? Glottometrics 11, 1-8.

Ferrer i Cancho, R., Riordan, O. & Bollobás, B. (2005). The consequences of Zipf's law for syntax and symbolic reference. Proceedings of the Royal Society of London B 272, 561-565.
[ doi: 10.1098/rspb.2004.2957 ]

Featured in Nature (News and views)

Ferrer i Cancho, R. (2005). The variation of Zipf's law in human language. European Physical Journal B 44, 249-257.
[ doi: 10.1140/epjb/e2005-00121-8 ]

Ferrer i Cancho, R. (2005). Decoding least effort and scaling in signal frequency distributions. Physica A 345, 275-284.
[ doi: 10.1016/j.physa.2004.06.158 ]

Ferrer i Cancho, R. (2004). Euclidean distance between syntactically linked words. Physical Review E 70, 056135.
[ doi: 10.1103/PhysRevE.70.056135 ]

Ferrer i Cancho, R., Solé, R. V. & Köhler, R. (2004). Patterns in syntactic dependency networks. Physical Review E 69, 051915.
[ doi: 10.1103/PhysRevE.69.051915 ]

Ferrer i Cancho, R. (2003). Language: universals, principles and origins. PhD Thesis. Barcelona: Universitat Politècnica de Catalunya.

Ferrer i Cancho, R. & Solé, R. V. (2003). Least effort and the origins of scaling in human language. Proceedings of the National Academy of Sciences USA 100, 788-791.
[ doi: 10.1073/pnas.0335980100 ]

Featured in Nature (Science Update)
Comments by the 1st author

Ferrer i Cancho & Solé, R. V.  (2003). Optimization in complex networks. Statistical Mechanics of Complex Networks, Lecture Notes in Physics Vol 625, Springer (Berlin), pp. 114-125.
[ doi: 10.1007/b12331 ]

Solé, R.V., Ferrer i Cancho, R., Montoya, J. M. & Valverde, S. (2002). Selection, tinkering and emergence in complex networks. Complexity 8, 20-33. 
[ doi: 10.1002/cplx.10055 ]

Valverde, S., Solé, R. V. & Ferrer i Cancho, R. (2002). Scale-free networks from optimal design. Europhysics Letters 60, 512-517.
[ doi: 10.1209/epl/i2002-00248-2 ]

Ferrer i Cancho, R. & Solé, R. V. (2002). Zipf´s law and random texts. Advances in Complex Systems 5, 1-6.
[ doi: 10.1142/S0219525902000468 ]

Ferrer i Cancho, R. & Reina, F. (2002). Quantifying the semantic contribution of particles. Journal of Quantitative Linguistics 9,  35-47.
[ doi: 10.1076/jqul. ]

Ferrer i Cancho, R. & Solé, R.V. (2001). The small-world of human language. Proceedings of the Royal Society of London B, 268, 2261-266.
[ doi: 10.1098/rspb.2001.1800 ]

Ferrer i Cancho, R., Janssen, C. & Solé, R. V. (2001). Topology of technology graphs: small world patterns in electronic circuits. Physical Review E 64, 046119.
[ doi: 10.1103/PhysRevE.64.046119 ]

Ferrer i Cancho, R. & Solé, R. V. (2001). Two regimes in the frequency of words and the origin of complex lexicons:  Zipf's law revisited. Journal of Quantitative Linguistics 8, 165-173.
[ doi: 10.1076/jqul. ]

Miralles, R., Ferrer, R., Moya, A., Solé, R.V. & Elena, S. (2001). Multiple infection dynamics has pronounced effects on the virulence of RNA viruses. Journal of Evolutionary Biology 14, 654-662.
[ doi:10.1046/j.1420-9101.2001.00308.x ]

Solé, R.V., Ferrer, R., González-García, I., Quer, J. & Domingo, E. (1999). Red queen dynamics, competition and critical points in a model of RNA virus quasispecies. Journal of Theoretical Biology 198, 47-59.
[ doi: 10.1006/jtbi.1999.0901 ]