Guo, Liujie; Gao, Fei; Zhan, Hui Existence, uniqueness and \(L^\infty\)-bound for weak solutions of a time fractional Keller-Segel system. (English) Zbl 1504.35620 Chaos Solitons Fractals 160, Article ID 112185, 17 p. (2022). MSC: 35R11 35Q92 35D30 26A33 PDFBibTeX XMLCite \textit{L. Guo} et al., Chaos Solitons Fractals 160, Article ID 112185, 17 p. (2022; Zbl 1504.35620) Full Text: DOI
Ghosh, Uttam; Pal, Swadesh; Banerjee, Malay Memory effect on Bazykin’s prey-predator model: stability and bifurcation analysis. (English) Zbl 1498.92161 Chaos Solitons Fractals 143, Article ID 110531, 10 p. (2021). MSC: 92D25 34A08 34C60 PDFBibTeX XMLCite \textit{U. Ghosh} et al., Chaos Solitons Fractals 143, Article ID 110531, 10 p. (2021; Zbl 1498.92161) Full Text: DOI
Danca, Marius-F.; Lampart, Marek Hidden and self-excited attractors in a heterogeneous Cournot oligopoly model. (English) Zbl 1496.91057 Chaos Solitons Fractals 142, Article ID 110371, 14 p. (2021). MSC: 91B55 37C70 PDFBibTeX XMLCite \textit{M.-F. Danca} and \textit{M. Lampart}, Chaos Solitons Fractals 142, Article ID 110371, 14 p. (2021; Zbl 1496.91057) Full Text: DOI arXiv
Rihan, F. A.; Rajivganthi, C. Dynamics of fractional-order delay differential model of prey-predator system with Holling-type III and infection among predators. (English) Zbl 1496.92095 Chaos Solitons Fractals 141, Article ID 110365, 14 p. (2020). MSC: 92D25 92D30 34K20 34K37 34K60 PDFBibTeX XMLCite \textit{F. A. Rihan} and \textit{C. Rajivganthi}, Chaos Solitons Fractals 141, Article ID 110365, 14 p. (2020; Zbl 1496.92095) Full Text: DOI
Kumar, Sunil; Kumar, Ajay; Samet, Bessem; Gómez-Aguilar, J. F.; Osman, M. S. A chaos study of tumor and effector cells in fractional tumor-immune model for cancer treatment. (English) Zbl 1496.92034 Chaos Solitons Fractals 141, Article ID 110321, 15 p. (2020). MSC: 92C50 PDFBibTeX XMLCite \textit{S. Kumar} et al., Chaos Solitons Fractals 141, Article ID 110321, 15 p. (2020; Zbl 1496.92034) Full Text: DOI
Wang, Lingyu; Sun, Kehui; Peng, Yuexi; He, Shaobo Chaos and complexity in a fractional-order higher-dimensional multicavity chaotic map. (English) Zbl 1495.39005 Chaos Solitons Fractals 131, Article ID 109488, 10 p. (2020). MSC: 39A13 39A33 26A33 PDFBibTeX XMLCite \textit{L. Wang} et al., Chaos Solitons Fractals 131, Article ID 109488, 10 p. (2020; Zbl 1495.39005) Full Text: DOI
Garmani, Hamid; Ait Omar, Driss; El Amrani, Mohamed; Baslam, Mohamed; Jourhmane, Mostafa Analysis of a dynamics duopoly game with two content providers. (English) Zbl 1495.37067 Chaos Solitons Fractals 131, Article ID 109466, 7 p. (2020). MSC: 37N40 91B54 91B55 91B52 PDFBibTeX XMLCite \textit{H. Garmani} et al., Chaos Solitons Fractals 131, Article ID 109466, 7 p. (2020; Zbl 1495.37067) Full Text: DOI
Sekerci, Yadigar Climate change effects on fractional order prey-predator model. (English) Zbl 1483.86004 Chaos Solitons Fractals 134, Article ID 109690, 16 p. (2020). MSC: 86A08 92D25 92D40 34A08 26A33 PDFBibTeX XMLCite \textit{Y. Sekerci}, Chaos Solitons Fractals 134, Article ID 109690, 16 p. (2020; Zbl 1483.86004) Full Text: DOI
Rihan, F. A.; Velmurugan, G. Dynamics of fractional-order delay differential model for tumor-immune system. (English) Zbl 1434.92017 Chaos Solitons Fractals 132, Article ID 109592, 14 p. (2020). MSC: 92C50 34K37 34D05 PDFBibTeX XMLCite \textit{F. A. Rihan} and \textit{G. Velmurugan}, Chaos Solitons Fractals 132, Article ID 109592, 14 p. (2020; Zbl 1434.92017) Full Text: DOI
Al-khedhairi, A.; Matouk, A. E.; Khan, I. Chaotic dynamics and chaos control for the fractional-order geomagnetic field model. (English) Zbl 1483.86010 Chaos Solitons Fractals 128, 390-401 (2019). MSC: 86A25 34A08 34C28 93C15 34C60 PDFBibTeX XMLCite \textit{A. Al-khedhairi} et al., Chaos Solitons Fractals 128, 390--401 (2019; Zbl 1483.86010) Full Text: DOI
Rihan, F. A.; Al-Mdallal, Q. M.; AlSakaji, H. J.; Hashish, A. A fractional-order epidemic model with time-delay and nonlinear incidence rate. (English) Zbl 1448.34148 Chaos Solitons Fractals 126, 97-105 (2019). MSC: 34K37 34K20 34K18 34K25 34D05 34D23 34K13 34K60 PDFBibTeX XMLCite \textit{F. A. Rihan} et al., Chaos Solitons Fractals 126, 97--105 (2019; Zbl 1448.34148) Full Text: DOI
Puu, Tonu; Tramontana, Fabio Can Bertrand and Cournot oligopolies be combined? (English) Zbl 1448.91166 Chaos Solitons Fractals 125, 97-107 (2019). MSC: 91B54 37N40 39A28 37M05 PDFBibTeX XMLCite \textit{T. Puu} and \textit{F. Tramontana}, Chaos Solitons Fractals 125, 97--107 (2019; Zbl 1448.91166) Full Text: DOI
Djilali, Salih Impact of prey herd shape on the predator-prey interaction. (English) Zbl 1448.92188 Chaos Solitons Fractals 120, 139-148 (2019). MSC: 92D25 34K18 34C23 34K60 PDFBibTeX XMLCite \textit{S. Djilali}, Chaos Solitons Fractals 120, 139--148 (2019; Zbl 1448.92188) Full Text: DOI
Bonyah, Ebenezer Chaos in a 5-D hyperchaotic system with four wings in the light of non-local and non-singular fractional derivatives. (English) Zbl 1442.34009 Chaos Solitons Fractals 116, 316-331 (2018). MSC: 34A08 34A12 34C60 PDFBibTeX XMLCite \textit{E. Bonyah}, Chaos Solitons Fractals 116, 316--331 (2018; Zbl 1442.34009) Full Text: DOI
Gori, Luca; Sodini, Mauro Price competition in a nonlinear differentiated duopoly. (English) Zbl 1380.91099 Chaos Solitons Fractals 104, 557-567 (2017). MSC: 91B54 91B55 37N40 37D45 PDFBibTeX XMLCite \textit{L. Gori} and \textit{M. Sodini}, Chaos Solitons Fractals 104, 557--567 (2017; Zbl 1380.91099) Full Text: DOI Link
Yang, Ruizhi Bifurcation analysis of a diffusive predator-prey system with Crowley-Martin functional response and delay. (English) Zbl 1373.92114 Chaos Solitons Fractals 95, 131-139 (2017). MSC: 92D25 35R10 35B35 PDFBibTeX XMLCite \textit{R. Yang}, Chaos Solitons Fractals 95, 131--139 (2017; Zbl 1373.92114) Full Text: DOI
Cavalli, Fausto; Naimzada, Ahmad Complex dynamics and multistability with increasing rationality in market games. (English) Zbl 1375.91156 Chaos Solitons Fractals 93, 151-161 (2016). MSC: 91B54 91B55 37N40 PDFBibTeX XMLCite \textit{F. Cavalli} and \textit{A. Naimzada}, Chaos Solitons Fractals 93, 151--161 (2016; Zbl 1375.91156) Full Text: DOI Link
Huang, Chengdai; Cao, Jinde; Xiao, Min Hybrid control on bifurcation for a delayed fractional gene regulatory network. (English) Zbl 1354.93073 Chaos Solitons Fractals 87, 19-29 (2016). MSC: 93C30 34H20 93C15 PDFBibTeX XMLCite \textit{C. Huang} et al., Chaos Solitons Fractals 87, 19--29 (2016; Zbl 1354.93073) Full Text: DOI
Peng, Yu; Lu, Qian; Xiao, Yue A dynamic Stackelberg duopoly model with different strategies. (English) Zbl 1415.91199 Chaos Solitons Fractals 85, 128-134 (2016). MSC: 91B54 91A65 34H10 34H20 PDFBibTeX XMLCite \textit{Y. Peng} et al., Chaos Solitons Fractals 85, 128--134 (2016; Zbl 1415.91199) Full Text: DOI
Askar, S. S.; Alnowibet, K. Nonlinear oligopolistic game with isoelastic demand function: rationality and local monopolistic approximation. (English) Zbl 1355.91046 Chaos Solitons Fractals 84, 15-22 (2016). MSC: 91B24 91B42 37N40 37C75 37M05 PDFBibTeX XMLCite \textit{S. S. Askar} and \textit{K. Alnowibet}, Chaos Solitons Fractals 84, 15--22 (2016; Zbl 1355.91046) Full Text: DOI
Brianzoni, Serena; Gori, Luca; Michetti, Elisabetta Dynamics of a Bertrand duopoly with differentiated products and nonlinear costs: analysis, comparisons and new evidences. (English) Zbl 1354.91086 Chaos Solitons Fractals 79, 191-203 (2015). MSC: 91B54 91B55 37N40 37M05 37C75 PDFBibTeX XMLCite \textit{S. Brianzoni} et al., Chaos Solitons Fractals 79, 191--203 (2015; Zbl 1354.91086) Full Text: DOI Link
Gori, Luca; Sodini, Mauro; Fanti, Luciano A nonlinear Cournot duopoly with advertising. (English) Zbl 1354.91091 Chaos Solitons Fractals 79, 178-190 (2015). MSC: 91B54 91B55 37N40 37M05 PDFBibTeX XMLCite \textit{L. Gori} et al., Chaos Solitons Fractals 79, 178--190 (2015; Zbl 1354.91091) Full Text: DOI Link
Kingni, S. T.; Nana, B.; Mbouna Ngueuteu, G. S.; Woafo, P.; Danckaert, J. Bursting oscillations in a 3D system with asymmetrically distributed equilibria: mechanism, electronic implementation and fractional derivation effect. (English) Zbl 1352.34060 Chaos Solitons Fractals 71, 29-40 (2015). MSC: 34C28 34C60 34A08 37D45 37M05 94C05 PDFBibTeX XMLCite \textit{S. T. Kingni} et al., Chaos Solitons Fractals 71, 29--40 (2015; Zbl 1352.34060) Full Text: DOI
Al-Hdaibat, Bashir; Govaerts, Willy; Neirynck, Niels On periodic and chaotic behavior in a two-dimensional monopoly model. (English) Zbl 1351.91018 Chaos Solitons Fractals 70, 27-37 (2015). MSC: 91B55 91B24 37N40 37M05 37C27 PDFBibTeX XMLCite \textit{B. Al-Hdaibat} et al., Chaos Solitons Fractals 70, 27--37 (2015; Zbl 1351.91018) Full Text: DOI
Tramontana, Fabio; Gardini, Laura; Puu, Tönu Mathematical properties of a discontinuous Cournot-Stackelberg model. (English) Zbl 1218.91114 Chaos Solitons Fractals 44, No. 1-3, 58-70 (2011). MSC: 91B52 91B24 PDFBibTeX XMLCite \textit{F. Tramontana} et al., Chaos Solitons Fractals 44, No. 1--3, 58--70 (2011; Zbl 1218.91114) Full Text: DOI
Tramontana, Fabio; Gardini, Laura; Puu, Tönu Global bifurcations in a piecewise-smooth Cournot duopoly game. (English) Zbl 1218.37068 Chaos Solitons Fractals 43, No. 1-12, 15-24 (2010). Reviewer: Vasile Postolică (Piatra Neamt) MSC: 37G35 37G30 PDFBibTeX XMLCite \textit{F. Tramontana} et al., Chaos Solitons Fractals 43, No. 1--12, 15--24 (2010; Zbl 1218.37068) Full Text: DOI
Ding, Zhanwen; Shi, Guiping Cooperation in a dynamical adjustment of duopoly game with incomplete information. (English) Zbl 1198.91081 Chaos Solitons Fractals 42, No. 2, 989-993 (2009). MSC: 91B26 PDFBibTeX XMLCite \textit{Z. Ding} and \textit{G. Shi}, Chaos Solitons Fractals 42, No. 2, 989--993 (2009; Zbl 1198.91081) Full Text: DOI
Puu, T.; Panchuk, A. Oligopoly and stability. (English) Zbl 1198.91116 Chaos Solitons Fractals 41, No. 5, 2505-2516 (2009). MSC: 91B54 PDFBibTeX XMLCite \textit{T. Puu} and \textit{A. Panchuk}, Chaos Solitons Fractals 41, No. 5, 2505--2516 (2009; Zbl 1198.91116) Full Text: DOI
Ma, Jun-Hai; Ji, Wei-Zhuo Complexity of repeated game model in electric power triopoly. (English) Zbl 1198.91037 Chaos Solitons Fractals 40, No. 4, 1735-1740 (2009). MSC: 91A20 91A23 68Q99 PDFBibTeX XMLCite \textit{J.-H. Ma} and \textit{W.-Z. Ji}, Chaos Solitons Fractals 40, No. 4, 1735--1740 (2009; Zbl 1198.91037) Full Text: DOI
Zhang, Jian-Gang; Li, Xian-Feng; Chu, Yan-Dong; Yu, Jian-Ning; Chang, Ying-Xiang Hopf bifurcations, Lyapunov exponents and control of chaos for a class of centrifugal flywheel governor system. (English) Zbl 1197.37067 Chaos Solitons Fractals 39, No. 5, 2150-2168 (2009). MSC: 37G99 PDFBibTeX XMLCite \textit{J.-G. Zhang} et al., Chaos Solitons Fractals 39, No. 5, 2150--2168 (2009; Zbl 1197.37067) Full Text: DOI
Elettreby, M. F. Two-prey one-predator model. (English) Zbl 1197.34095 Chaos Solitons Fractals 39, No. 5, 2018-2027 (2009). MSC: 34D20 92D25 PDFBibTeX XMLCite \textit{M. F. Elettreby}, Chaos Solitons Fractals 39, No. 5, 2018--2027 (2009; Zbl 1197.34095) Full Text: DOI
Abdulrahman, A. A.; Elrifai, E. A. Closed periodic orbits of convective solutions in rapidly rotating system: Double torus knots and links, DTK. (English) Zbl 1152.76385 Chaos Solitons Fractals 36, No. 1, 25-31 (2008). MSC: 76E06 37C25 PDFBibTeX XMLCite \textit{A. A. Abdulrahman} and \textit{E. A. Elrifai}, Chaos Solitons Fractals 36, No. 1, 25--31 (2008; Zbl 1152.76385) Full Text: DOI
Asker, S. S. On dynamical multi-team Cournot game in exploitation of a renewable resource. (English) Zbl 1133.91510 Chaos Solitons Fractals 32, No. 1, 264-268 (2007). MSC: 91B76 37N40 91A50 PDFBibTeX XMLCite \textit{S. S. Asker}, Chaos Solitons Fractals 32, No. 1, 264--268 (2007; Zbl 1133.91510) Full Text: DOI
Huang, Dongwei; Wang, Hongli; Zhu, Zhiwen; Zhang, Feng Stochastic stability of four-wheel-steering system. (English) Zbl 1131.70010 Chaos Solitons Fractals 33, No. 3, 823-828 (2007). MSC: 70L05 70H14 PDFBibTeX XMLCite \textit{D. Huang} et al., Chaos Solitons Fractals 33, No. 3, 823--828 (2007; Zbl 1131.70010) Full Text: DOI
Stefanini, Luciano; Sorini, Laerte; Guerra, Maria Letizia Simulation of fuzzy dynamical systems using the LU-representation of fuzzy numbers. (English) Zbl 1142.37372 Chaos Solitons Fractals 29, No. 3, 638-652 (2006). MSC: 37M05 PDFBibTeX XMLCite \textit{L. Stefanini} et al., Chaos Solitons Fractals 29, No. 3, 638--652 (2006; Zbl 1142.37372) Full Text: DOI
Elettreby, M. F.; Hassan, S. Z. Dynamical multi-team Cournot game. (English) Zbl 1121.91019 Chaos Solitons Fractals 27, No. 3, 666-672 (2006). MSC: 91A25 PDFBibTeX XMLCite \textit{M. F. Elettreby} and \textit{S. Z. Hassan}, Chaos Solitons Fractals 27, No. 3, 666--672 (2006; Zbl 1121.91019) Full Text: DOI
Wang, Ruiqi; Deng, Jin; Jing, Zhujun Chaos control in Duffing system. (English) Zbl 1091.37013 Chaos Solitons Fractals 27, No. 1, 249-257 (2006). MSC: 37D45 93D15 34C28 PDFBibTeX XMLCite \textit{R. Wang} et al., Chaos Solitons Fractals 27, No. 1, 249--257 (2006; Zbl 1091.37013) Full Text: DOI
Cafagna, Vittorio; Coccorese, Paolo Dynamical systems and the arising of cooperation in a Cournot duopoly. (English) Zbl 1111.91012 Chaos Solitons Fractals 25, No. 3, 655-664 (2005). MSC: 91B26 PDFBibTeX XMLCite \textit{V. Cafagna} and \textit{P. Coccorese}, Chaos Solitons Fractals 25, No. 3, 655--664 (2005; Zbl 1111.91012) Full Text: DOI
Wang, Ruiqi; Jing, Zhujun Chaos control of chaotic pendulum system. (English) Zbl 1045.37016 Chaos Solitons Fractals 21, No. 1, 201-207 (2004). MSC: 37D45 70K55 93D15 PDFBibTeX XMLCite \textit{R. Wang} and \textit{Z. Jing}, Chaos Solitons Fractals 21, No. 1, 201--207 (2004; Zbl 1045.37016) Full Text: DOI
Puu, Tönu; Norin, Anna Cournot duopoly when the competitors operate under capacity constraints. (English) Zbl 1060.91096 Chaos Solitons Fractals 18, No. 3, 577-592 (2003). MSC: 91B62 91B52 37N40 91A25 91B38 PDFBibTeX XMLCite \textit{T. Puu} and \textit{A. Norin}, Chaos Solitons Fractals 18, No. 3, 577--592 (2003; Zbl 1060.91096) Full Text: DOI
Yassen, M. T. Chaos control of Chen chaotic dynamical system. (English) Zbl 1038.37029 Chaos Solitons Fractals 15, No. 2, 271-283 (2003). MSC: 37D45 93C10 37N35 PDFBibTeX XMLCite \textit{M. T. Yassen}, Chaos Solitons Fractals 15, No. 2, 271--283 (2003; Zbl 1038.37029) Full Text: DOI
Wang, Qiuping A. Quantum gas distribution prescribed by factorization hypothesis of probability. (English) Zbl 0995.82509 Chaos Solitons Fractals 14, No. 5, 765-770 (2002). MSC: 82C10 PDFBibTeX XMLCite \textit{Q. A. Wang}, Chaos Solitons Fractals 14, No. 5, 765--770 (2002; Zbl 0995.82509) Full Text: DOI arXiv
Agiza, H. N.; Hegazi, A. S.; Elsadany, A. A. The dynamics of Bowley’s model with bounded rationality. (English) Zbl 1036.91004 Chaos Solitons Fractals 12, No. 9, 1705-1717 (2001). Reviewer: Prabhat Kumar Mahanti (Saint John) MSC: 91A25 37N40 91B26 PDFBibTeX XMLCite \textit{H. N. Agiza} et al., Chaos Solitons Fractals 12, No. 9, 1705--1717 (2001; Zbl 1036.91004) Full Text: DOI
Hegazi, A.; Mansour, M. Irreducible representation of the quantum group \(E_q(2)\). (English) Zbl 1062.17011 Chaos Solitons Fractals 12, No. 9, 1687-1690 (2001). MSC: 17B37 81R50 81R12 PDFBibTeX XMLCite \textit{A. Hegazi} and \textit{M. Mansour}, Chaos Solitons Fractals 12, No. 9, 1687--1690 (2001; Zbl 1062.17011) Full Text: DOI
Wang, Qiuping A. Incomplete statistics: Nonextensive generalizations of statistical mechanics. (English) Zbl 1022.82001 Chaos Solitons Fractals 12, No. 8, 1431-1437 (2001). MSC: 82B03 81P20 94A17 PDFBibTeX XMLCite \textit{Q. A. Wang}, Chaos Solitons Fractals 12, No. 8, 1431--1437 (2001; Zbl 1022.82001) Full Text: DOI arXiv
Hegazi, A.; Agiza, H. N.; El-Dessoky, M. M. Controlling chaotic behaviour for spin generator and Rössler dynamical systems with feedback control. (English) Zbl 1016.37050 Chaos Solitons Fractals 12, No. 4, 631-658 (2001). MSC: 37N35 93D15 PDFBibTeX XMLCite \textit{A. Hegazi} et al., Chaos Solitons Fractals 12, No. 4, 631--658 (2001; Zbl 1016.37050) Full Text: DOI
Ahmed, E.; El-Rifai, E. A. Knots motivated by discrete dynamical systems. (English) Zbl 0994.57010 Chaos Solitons Fractals 12, No. 13, 2471-2474 (2001). MSC: 57M25 91B64 PDFBibTeX XMLCite \textit{E. Ahmed} and \textit{E. A. El-Rifai}, Chaos Solitons Fractals 12, No. 13, 2471--2474 (2001; Zbl 0994.57010) Full Text: DOI
Agliari, Anna; Gardini, Laura; Puu, Tönu The dynamics of a tripoly Cournot game. (English) Zbl 0998.91035 Chaos Solitons Fractals 11, No. 15, 2531-2560 (2000). Reviewer: Nikolay Nikolajevich Ivanov (Grodno) MSC: 91B54 91A10 91A70 PDFBibTeX XMLCite \textit{A. Agliari} et al., Chaos Solitons Fractals 11, No. 15, 2531--2560 (2000; Zbl 0998.91035) Full Text: DOI
El-Rifai, E. A. A generalization of Lotka-Volterra, GLV, systems with some dynamical and topological properties. (English) Zbl 0955.92035 Chaos Solitons Fractals 11, No. 11, 1747-1751 (2000). MSC: 92D40 37N25 92D25 34D05 PDFBibTeX XMLCite \textit{E. A. El-Rifai}, Chaos Solitons Fractals 11, No. 11, 1747--1751 (2000; Zbl 0955.92035) Full Text: DOI
Agiza, H. N. On the analysis of stability, bifurcation, chaos and chaos control of Kopel map. (English) Zbl 0955.37022 Chaos Solitons Fractals 10, No. 11, 1909-1916 (1999). Reviewer: Messoud Efendiev (Berlin) MSC: 37E30 37N40 37C75 37D45 37C35 65P30 PDFBibTeX XMLCite \textit{H. N. Agiza}, Chaos Solitons Fractals 10, No. 11, 1909--1916 (1999; Zbl 0955.37022) Full Text: DOI
El-Rifai, E. A.; El-Massri, Y. A. Some calculations on link polynomials from 2-parameter quantum groups. (English) Zbl 0948.57009 Chaos Solitons Fractals 10, No. 9, 1555-1558 (1999). MSC: 57M27 17B37 57M25 81R50 PDFBibTeX XMLCite \textit{E. A. El-Rifai} and \textit{Y. A. El-Massri}, Chaos Solitons Fractals 10, No. 9, 1555--1558 (1999; Zbl 0948.57009) Full Text: DOI
Ahmed, E.; Agiza, H. N.; Hassan, S. Z. On modelling advertisement in Cournot duopoly. (English) Zbl 0957.91066 Chaos Solitons Fractals 10, No. 7, 1179-1184 (1999). MSC: 91B54 37N40 37D45 PDFBibTeX XMLCite \textit{E. Ahmed} et al., Chaos Solitons Fractals 10, No. 7, 1179--1184 (1999; Zbl 0957.91066) Full Text: DOI
El-Rifai, E. A. Necessary and sufficient condition for Lorenz knots to be closed under satellite construction. (English) Zbl 0948.57003 Chaos Solitons Fractals 10, No. 1, 137-146 (1999). Reviewer: Weiping Li (Stillwater) MSC: 57M25 PDFBibTeX XMLCite \textit{E. A. El-Rifai}, Chaos Solitons Fractals 10, No. 1, 137--146 (1999; Zbl 0948.57003) Full Text: DOI