Shanmugam, Saravanan; Syed Ali, M.; Vadivel, R.; Lee, Gyu M. Finite-time \(H_\infty\) state estimation for Markovian jump neural networks with time-varying delays via an extended Wirtinger’s integral inequality. (English) Zbl 1512.93149 Math. Probl. Eng. 2021, Article ID 5558955, 18 p. (2021). MSC: 93E15 92B20 34K20 PDFBibTeX XMLCite \textit{S. Shanmugam} et al., Math. Probl. Eng. 2021, Article ID 5558955, 18 p. (2021; Zbl 1512.93149) Full Text: DOI
Ibrahim, Wubshet; Bijiga, Lelisa Kebena Neural network method for solving time-fractional telegraph equation. (English) Zbl 1512.35621 Math. Probl. Eng. 2021, Article ID 7167801, 10 p. (2021). MSC: 35R11 68T07 PDFBibTeX XMLCite \textit{W. Ibrahim} and \textit{L. K. Bijiga}, Math. Probl. Eng. 2021, Article ID 7167801, 10 p. (2021; Zbl 1512.35621) Full Text: DOI
Yu, Lina; Ma, Yunfei; Yang, Yuntong; Zhang, Jingchao; Wang, Chunwei Robust fixed-time synchronization for coupled delayed neural networks with discontinuous activations subject to a quadratic polynomial growth. (English) Zbl 1512.93004 Math. Probl. Eng. 2021, Article ID 6614150, 13 p. (2021). MSC: 93A14 93A15 34D06 92B20 93B12 93D40 PDFBibTeX XMLCite \textit{L. Yu} et al., Math. Probl. Eng. 2021, Article ID 6614150, 13 p. (2021; Zbl 1512.93004) Full Text: DOI
Naifar, Omar; Jmal, Assaad; Nagy, A. M.; Ben Makhlouf, Abdellatif Improved quasiuniform stability for fractional order neural nets with mixed delay. (English) Zbl 1459.34181 Math. Probl. Eng. 2020, Article ID 8811226, 7 p. (2020). MSC: 34K37 34K20 45J05 92B20 PDFBibTeX XMLCite \textit{O. Naifar} et al., Math. Probl. Eng. 2020, Article ID 8811226, 7 p. (2020; Zbl 1459.34181) Full Text: DOI
Zhou, Wenbo; Li, Biwen; Zhang, Jin-E Matrix measure approach for stability and synchronization of complex-valued neural networks with deviating argument. (English) Zbl 1459.34173 Math. Probl. Eng. 2020, Article ID 8877129, 16 p. (2020). MSC: 34K20 93D23 92B20 PDFBibTeX XMLCite \textit{W. Zhou} et al., Math. Probl. Eng. 2020, Article ID 8877129, 16 p. (2020; Zbl 1459.34173) Full Text: DOI
Tang, Bingnan Bifurcation study on fractional-order Cohen-Grossberg neural networks involving delays. (English) Zbl 1459.34164 Math. Probl. Eng. 2020, Article ID 8833366, 16 p. (2020). MSC: 34K18 34K20 92B20 PDFBibTeX XMLCite \textit{B. Tang}, Math. Probl. Eng. 2020, Article ID 8833366, 16 p. (2020; Zbl 1459.34164) Full Text: DOI
Thoiyab, N. Mohamed; Muruganantham, P.; Rajchakit, Grienggrai; Gunasekaran, Nallappan; Unyong, Bundit; Humphries, Usa; Kaewmesri, Pramet; Lim, Chee Peng Global stability analysis of neural networks with constant time delay via Frobenius norm. (English) Zbl 1459.93142 Math. Probl. Eng. 2020, Article ID 4321312, 14 p. (2020). MSC: 93D09 92B20 93D20 34K20 PDFBibTeX XMLCite \textit{N. M. Thoiyab} et al., Math. Probl. Eng. 2020, Article ID 4321312, 14 p. (2020; Zbl 1459.93142) Full Text: DOI
Zhen, Bin; Zhang, Dingyi; Song, Zigen Complexity induced by external stimulations in a neural network system with time delay. (English) Zbl 1459.34172 Math. Probl. Eng. 2020, Article ID 5472351, 9 p. (2020). MSC: 34K20 34K18 92C20 92B20 PDFBibTeX XMLCite \textit{B. Zhen} et al., Math. Probl. Eng. 2020, Article ID 5472351, 9 p. (2020; Zbl 1459.34172) Full Text: DOI
Liu, Shuai; Chen, Chuan; Peng, Haipeng Fixed-time synchronization of neural networks with discrete delay. (English) Zbl 1459.93009 Math. Probl. Eng. 2020, Article ID 7830547, 9 p. (2020). MSC: 93A14 34D06 34K35 92B20 93D40 93B52 PDFBibTeX XMLCite \textit{S. Liu} et al., Math. Probl. Eng. 2020, Article ID 7830547, 9 p. (2020; Zbl 1459.93009) Full Text: DOI
Yan, Hongyun; Qiao, Yuanhua; Duan, Lijuan; Zhang, Ling Global Mittag-Leffler stabilization of fractional-order BAM neural networks with linear state feedback controllers. (English) Zbl 1459.93149 Math. Probl. Eng. 2020, Article ID 6398208, 10 p. (2020). MSC: 93D15 34A08 34H15 92B20 PDFBibTeX XMLCite \textit{H. Yan} et al., Math. Probl. Eng. 2020, Article ID 6398208, 10 p. (2020; Zbl 1459.93149) Full Text: DOI
Fang, Jie; Zhang, Yin; Xu, Danying; Sun, Junwei Synchronization of time delay coupled neural networks based on impulsive control. (English) Zbl 1459.93007 Math. Probl. Eng. 2020, Article ID 5986018, 8 p. (2020). MSC: 93A14 34D06 93B70 93C27 34K35 92B20 PDFBibTeX XMLCite \textit{J. Fang} et al., Math. Probl. Eng. 2020, Article ID 5986018, 8 p. (2020; Zbl 1459.93007) Full Text: DOI
Stojanovic, Sreten; Stojanovic, Milan; Stevanovic, Milos Novel delay-dependent stability criteria for discrete-time neural networks with time-varying delay. (English) Zbl 1427.93181 Math. Probl. Eng. 2018, Article ID 5397870, 15 p. (2018). MSC: 93D05 93C55 39A60 34K20 92B20 PDFBibTeX XMLCite \textit{S. Stojanovic} et al., Math. Probl. Eng. 2018, Article ID 5397870, 15 p. (2018; Zbl 1427.93181) Full Text: DOI
Li, Xiaofei; Qin, Chuan; Zhu, Quanxin Exponential stability of antiperiodic solution for BAM neural networks with time-varying delays. (English) Zbl 1426.34100 Math. Probl. Eng. 2018, Article ID 3034794, 13 p. (2018). MSC: 34K20 34D23 92B20 PDFBibTeX XMLCite \textit{X. Li} et al., Math. Probl. Eng. 2018, Article ID 3034794, 13 p. (2018; Zbl 1426.34100) Full Text: DOI
Meng, Bo; Wang, Xiaohong Adaptive synchronization for uncertain delayed fractional-order Hopfield neural networks via fractional-order sliding mode control. (English) Zbl 1426.34016 Math. Probl. Eng. 2018, Article ID 1603629, 8 p. (2018). MSC: 34A08 34D06 34K37 92B20 93A14 93B12 93C40 PDFBibTeX XMLCite \textit{B. Meng} and \textit{X. Wang}, Math. Probl. Eng. 2018, Article ID 1603629, 8 p. (2018; Zbl 1426.34016) Full Text: DOI
Puebla, Hector; Hernández-Martínez, Eliseo; Rodriguez-Jara, Mariana; Lopez-Monsalvo, Cesar S. Robust master-slave synchronization of neuronal systems. (English) Zbl 1426.34077 Math. Probl. Eng. 2017, Article ID 7587294, 10 p. (2017). MSC: 34H05 34D06 92B20 93C15 PDFBibTeX XMLCite \textit{H. Puebla} et al., Math. Probl. Eng. 2017, Article ID 7587294, 10 p. (2017; Zbl 1426.34077) Full Text: DOI
Shi, Jingping; Wu, Zhonghua; Lu, Jingchao Constrained adaptive neural control of nonlinear strict-feedback systems with input dead-zone. (English) Zbl 1426.93144 Math. Probl. Eng. 2017, Article ID 2981518, 11 p. (2017). MSC: 93C40 93C10 92B20 93B51 PDFBibTeX XMLCite \textit{J. Shi} et al., Math. Probl. Eng. 2017, Article ID 2981518, 11 p. (2017; Zbl 1426.93144) Full Text: DOI
Zhang, Weiwei; Cao, Jinde; Alsaedi, Ahmed; Alsaadi, Fuad E. New methods of finite-time synchronization for a class of fractional-order delayed neural networks. (English) Zbl 1426.34069 Math. Probl. Eng. 2017, Article ID 1804383, 9 p. (2017). MSC: 34D06 34K20 34A08 34K37 92B20 93C15 PDFBibTeX XMLCite \textit{W. Zhang} et al., Math. Probl. Eng. 2017, Article ID 1804383, 9 p. (2017; Zbl 1426.34069) Full Text: DOI
Zhang, Jin-E Analysis and design of associative memories for memristive neural networks with deviating argument. (English) Zbl 1426.34107 Math. Probl. Eng. 2017, Article ID 1057909, 16 p. (2017). MSC: 34K20 92B20 34K19 93D20 94C30 PDFBibTeX XMLCite \textit{J.-E Zhang}, Math. Probl. Eng. 2017, Article ID 1057909, 16 p. (2017; Zbl 1426.34107) Full Text: DOI
Rao, Ruofeng; Pu, Zhilin; Zhong, Shouming; Li, Xinggui Fixed points and exponential stability for impulsive time-delays BAM neural networks via LMI approach and contraction mapping principle. (English) Zbl 1400.34119 Math. Probl. Eng. 2016, Article ID 3154683, 8 p. (2016). MSC: 34K20 34K45 92B20 PDFBibTeX XMLCite \textit{R. Rao} et al., Math. Probl. Eng. 2016, Article ID 3154683, 8 p. (2016; Zbl 1400.34119) Full Text: DOI
Lu, Zhenyu; Li, Kai; Li, Yan Global asymptotic stability of switched neural networks with delays. (English) Zbl 1394.92007 Math. Probl. Eng. 2015, Article ID 717513, 11 p. (2015). MSC: 92B20 34D23 34K20 PDFBibTeX XMLCite \textit{Z. Lu} et al., Math. Probl. Eng. 2015, Article ID 717513, 11 p. (2015; Zbl 1394.92007) Full Text: DOI
Park, M. J.; Kwon, O. M.; Cha, E. J. On stability analysis for generalized neural networks with time-varying delays. (English) Zbl 1394.34153 Math. Probl. Eng. 2015, Article ID 387805, 11 p. (2015). MSC: 34K20 92B20 93D05 PDFBibTeX XMLCite \textit{M. J. Park} et al., Math. Probl. Eng. 2015, Article ID 387805, 11 p. (2015; Zbl 1394.34153) Full Text: DOI
Xiang, Xuyan; Wu, Jianguo Dynamics of moment neuronal networks with intra- and inter-interactions. (English) Zbl 1394.92009 Math. Probl. Eng. 2015, Article ID 381271, 13 p. (2015). MSC: 92B20 PDFBibTeX XMLCite \textit{X. Xiang} and \textit{J. Wu}, Math. Probl. Eng. 2015, Article ID 381271, 13 p. (2015; Zbl 1394.92009) Full Text: DOI
Rao, Ruofeng; Wang, Xiongrui; Zhong, Shouming LMI-based stability criterion for impulsive delays Markovian jumping time-delays reaction-diffusion BAM neural networks via Gronwall-Bellman-type impulsive integral inequality. (English) Zbl 1394.93350 Math. Probl. Eng. 2015, Article ID 185854, 11 p. (2015). MSC: 93E15 34D23 60J27 68T05 92B20 PDFBibTeX XMLCite \textit{R. Rao} et al., Math. Probl. Eng. 2015, Article ID 185854, 11 p. (2015; Zbl 1394.93350) Full Text: DOI
Zhu, Hongying; Feng, Chunhua Existence and global uniform asymptotic stability of pseudo almost periodic solutions for Cohen-Grossberg neural networks with discrete and distributed delays. (English) Zbl 1407.34108 Math. Probl. Eng. 2014, Article ID 968404, 10 p. (2014). MSC: 34K20 92B20 34K13 PDFBibTeX XMLCite \textit{H. Zhu} and \textit{C. Feng}, Math. Probl. Eng. 2014, Article ID 968404, 10 p. (2014; Zbl 1407.34108) Full Text: DOI
Yu, Hongshan; Peng, Jinzhu; Tang, Yandong Identification of nonlinear dynamic systems using Hammerstein-type neural network. (English) Zbl 1407.93097 Math. Probl. Eng. 2014, Article ID 959507, 9 p. (2014). MSC: 93B30 92B20 PDFBibTeX XMLCite \textit{H. Yu} et al., Math. Probl. Eng. 2014, Article ID 959507, 9 p. (2014; Zbl 1407.93097) Full Text: DOI
Shao, Lei; Huang, He; Zhao, Heming; Huang, Tingwen Delay-dependent state estimation of static neural networks with time-varying and distributed delays. (English) Zbl 1407.93375 Math. Probl. Eng. 2014, Article ID 951973, 9 p. (2014). MSC: 93E10 92B20 PDFBibTeX XMLCite \textit{L. Shao} et al., Math. Probl. Eng. 2014, Article ID 951973, 9 p. (2014; Zbl 1407.93375) Full Text: DOI
Lou, Xuyang Stochastic resonance in neuronal network motifs with Ornstein-Uhlenbeck colored noise. (English) Zbl 1407.92013 Math. Probl. Eng. 2014, Article ID 902395, 7 p. (2014). MSC: 92B20 34F15 PDFBibTeX XMLCite \textit{X. Lou}, Math. Probl. Eng. 2014, Article ID 902395, 7 p. (2014; Zbl 1407.92013) Full Text: DOI
Xiao, Lei; Chen, Xiaohui; Zhang, Xinghui A joint optimization of momentum item and Levenberg-Marquardt algorithm to level up the BPNN’s generalization ability. (English) Zbl 1407.68419 Math. Probl. Eng. 2014, Article ID 653072, 10 p. (2014). MSC: 68T05 92B20 PDFBibTeX XMLCite \textit{L. Xiao} et al., Math. Probl. Eng. 2014, Article ID 653072, 10 p. (2014; Zbl 1407.68419) Full Text: DOI
Kwon, O. M.; Park, M. J.; Park, Ju H.; Lee, S. M.; Cha, E. J. Analysis on passivity for uncertain neural networks with time-varying delays. (English) Zbl 1407.93312 Math. Probl. Eng. 2014, Article ID 602828, 10 p. (2014). MSC: 93D05 92B20 93D20 PDFBibTeX XMLCite \textit{O. M. Kwon} et al., Math. Probl. Eng. 2014, Article ID 602828, 10 p. (2014; Zbl 1407.93312) Full Text: DOI
Ren, Shun-Yan; Zhao, Yue-Hui Stability and passivity of spatially and temporally complex dynamical networks with time-varying delays. (English) Zbl 1407.35102 Math. Probl. Eng. 2014, Article ID 412169, 8 p. (2014). MSC: 35K51 35K57 35Q92 35B35 92B20 PDFBibTeX XMLCite \textit{S.-Y. Ren} and \textit{Y.-H. Zhao}, Math. Probl. Eng. 2014, Article ID 412169, 8 p. (2014; Zbl 1407.35102) Full Text: DOI
Pei, Yangjun; Liu, Chao; Han, Qi Stability of delayed Hopfield neural networks with variable-time impulses. (English) Zbl 1407.92014 Math. Probl. Eng. 2014, Article ID 154036, 6 p. (2014). MSC: 92B20 37N25 PDFBibTeX XMLCite \textit{Y. Pei} et al., Math. Probl. Eng. 2014, Article ID 154036, 6 p. (2014; Zbl 1407.92014) Full Text: DOI
Wan, Min; Gou, Jianping; Wang, Desong; Wang, Xiaoming Dynamical properties of discrete-time background neural networks with uniform firing rate. (English) Zbl 1299.37072 Math. Probl. Eng. 2013, Article ID 892794, 6 p. (2013). MSC: 37N35 39A05 65Q30 92B20 PDFBibTeX XMLCite \textit{M. Wan} et al., Math. Probl. Eng. 2013, Article ID 892794, 6 p. (2013; Zbl 1299.37072) Full Text: DOI
Sun, Yunshan; Zhang, Liyi; Zhang, Jin; Shi, Lijuan Neural network blind equalization algorithm applied to medical CT image restoration. (English) Zbl 1299.92010 Math. Probl. Eng. 2013, Article ID 743546, 10 p. (2013). MSC: 92B20 92C50 94A08 PDFBibTeX XMLCite \textit{Y. Sun} et al., Math. Probl. Eng. 2013, Article ID 743546, 10 p. (2013; Zbl 1299.92010)
Wang, Lidan; Duan, Meitao; Duan, Shukai Memristive Chebyshev neural network and its applications in function approximation. (English) Zbl 1296.94180 Math. Probl. Eng. 2013, Article ID 429402, 7 p. (2013). MSC: 94C05 92B20 41A30 PDFBibTeX XMLCite \textit{L. Wang} et al., Math. Probl. Eng. 2013, Article ID 429402, 7 p. (2013; Zbl 1296.94180)
Mao, Zisen; Wang, Hao; Xu, Dandan; Cui, Zhoujin Bifurcation and hybrid control for a simple Hopfield neural networks with delays. (English) Zbl 1296.34153 Math. Probl. Eng. 2013, Article ID 315367, 8 p. (2013). MSC: 34K14 92B20 PDFBibTeX XMLCite \textit{Z. Mao} et al., Math. Probl. Eng. 2013, Article ID 315367, 8 p. (2013; Zbl 1296.34153)
Alanis, Alma Y.; Ricalde, Luis J.; Simetti, Chiara; Odone, Francesca Neural model with particle swarm optimization Kalman learning for forecasting in smart grids. (English) Zbl 1296.93191 Math. Probl. Eng. 2013, Article ID 197690, 9 p. (2013). MSC: 93E11 90B15 90C59 62M10 92B20 PDFBibTeX XMLCite \textit{A. Y. Alanis} et al., Math. Probl. Eng. 2013, Article ID 197690, 9 p. (2013; Zbl 1296.93191)
Wu, Huaiqin; Li, Ning; Wang, Kewang; Xu, Guohua; Guo, Qiangqiang Global robust stability of switched interval neural networks with discrete and distributed time-varying delays of neural type. (English) Zbl 1264.34145 Math. Probl. Eng. 2012, Article ID 361871, 18 p. (2012). MSC: 34K20 93D09 34K34 34K40 92B20 PDFBibTeX XMLCite \textit{H. Wu} et al., Math. Probl. Eng. 2012, Article ID 361871, 18 p. (2012; Zbl 1264.34145) Full Text: DOI
Tsai, Zhi-Ren; Hwang, Jiing-Dong \(H_{\infty}\) neural-network-based discrete-time fuzzy control of continuous-time nonlinear systems with dither. (English) Zbl 1264.93136 Math. Probl. Eng. 2012, Article ID 314964, 18 p. (2012). MSC: 93C42 93B36 93C83 92B20 93C55 PDFBibTeX XMLCite \textit{Z.-R. Tsai} and \textit{J.-D. Hwang}, Math. Probl. Eng. 2012, Article ID 314964, 18 p. (2012; Zbl 1264.93136) Full Text: DOI
Zhang, Haitao; Li, Tao; Fei, Shumin Synchronization for an array of coupled Cohen-Grossberg neural networks with time-varying delay. (English) Zbl 1213.93110 Math. Probl. Eng. 2011, Article ID 831695, 22 p. (2011). MSC: 93C40 92B20 PDFBibTeX XMLCite \textit{H. Zhang} et al., Math. Probl. Eng. 2011, Article ID 831695, 22 p. (2011; Zbl 1213.93110) Full Text: DOI EuDML
Minh, Vu Trieu; Hashim, Fakhruldin Mohd Adaptive teleoperation system with neural network-based multiple model control. (English) Zbl 1205.93082 Math. Probl. Eng. 2010, Article ID 592054, 15 p. (2010). MSC: 93C40 92B20 93B35 PDFBibTeX XMLCite \textit{V. T. Minh} and \textit{F. M. Hashim}, Math. Probl. Eng. 2010, Article ID 592054, 15 p. (2010; Zbl 1205.93082) Full Text: DOI EuDML
Wu, Huaiqin; Shi, Rui; Qin, Leijie; Tao, Feng; He, Lijun A nonlinear projection neural network for solving interval quadratic programming problems and its stability analysis. (English) Zbl 1195.90072 Math. Probl. Eng. 2010, Article ID 403749, 13 p. (2010). MSC: 90C20 92B20 PDFBibTeX XMLCite \textit{H. Wu} et al., Math. Probl. Eng. 2010, Article ID 403749, 13 p. (2010; Zbl 1195.90072) Full Text: DOI EuDML
Mattioli, Gianni; Scalia, Massimo; Cattani, Carlo Analysis of large-amplitude pulses in short time intervals: application to neuron interactions. (English) Zbl 1189.37099 Math. Probl. Eng. 2010, Article ID 895785, 15 p. (2010). MSC: 37N25 92B20 PDFBibTeX XMLCite \textit{G. Mattioli} et al., Math. Probl. Eng. 2010, Article ID 895785, 15 p. (2010; Zbl 1189.37099) Full Text: DOI EuDML
Yang, Woosung; Kwon, Jaesung; Chong, Nak Young; Oh, Yonghwan Biologically inspired robotic arm control using an artificial neural oscillator. (English) Zbl 1191.93111 Math. Probl. Eng. 2010, Article ID 107538, 16 p. (2010). MSC: 93C85 92B20 PDFBibTeX XMLCite \textit{W. Yang} et al., Math. Probl. Eng. 2010, Article ID 107538, 16 p. (2010; Zbl 1191.93111) Full Text: DOI EuDML
Zhao, Kaihong; Li, Yongkun Robust stability analysis of fuzzy neural network with delays. (English) Zbl 1190.93080 Math. Probl. Eng. 2009, Article ID 826908, 13 p. (2009). MSC: 93D09 93C42 92B20 PDFBibTeX XMLCite \textit{K. Zhao} and \textit{Y. Li}, Math. Probl. Eng. 2009, Article ID 826908, 13 p. (2009; Zbl 1190.93080) Full Text: DOI EuDML
Fan, Dejun; Wei, Junjie Equivariant Hopf bifurcation in a ring of identical cells with delay. (English) Zbl 1182.37035 Math. Probl. Eng. 2009, Article ID 950251, 34 p. (2009). MSC: 37G40 34C23 92B20 92C37 PDFBibTeX XMLCite \textit{D. Fan} and \textit{J. Wei}, Math. Probl. Eng. 2009, Article ID 950251, 34 p. (2009; Zbl 1182.37035) Full Text: DOI EuDML
Yang, Yong; Wang, Guoyin; Kong, Hao Self-learning facial emotional feature selection based on rough set theory. (English) Zbl 1191.68541 Math. Probl. Eng. 2009, Article ID 802932, 16 p. (2009). MSC: 68T05 92B20 68T10 68T30 PDFBibTeX XMLCite \textit{Y. Yang} et al., Math. Probl. Eng. 2009, Article ID 802932, 16 p. (2009; Zbl 1191.68541) Full Text: DOI EuDML
Cheng, Wushan Intelligent control of the complex technology process based on adaptive pattern clustering and feature map. (English) Zbl 1162.93360 Math. Probl. Eng. 2008, Article ID 783278, 9 p. (2008). MSC: 93C40 92B20 93C42 62D05 PDFBibTeX XMLCite \textit{W. Cheng}, Math. Probl. Eng. 2008, Article ID 783278, 9 p. (2008; Zbl 1162.93360) Full Text: DOI EuDML
Liu, Xinzhi; Shen, Xuemin; Zhang, Yi Absolute stability of nonlinear systems with time delays and applications to neural networks. (English) Zbl 1014.34066 Math. Probl. Eng. 7, No. 5, 413-431 (2001). MSC: 34K20 92B20 34H05 49J25 PDFBibTeX XMLCite \textit{X. Liu} et al., Math. Probl. Eng. 7, No. 5, 413--431 (2001; Zbl 1014.34066) Full Text: DOI EuDML
Reyes-Reyes, J.; Yu, W.; Poznyak, A. S. Passivation and control of partially known SISO nonlinear systems via dynamic neural networks. (English) Zbl 0988.93073 Math. Probl. Eng. 6, No. 1, 61-83 (2000). Reviewer: Ladislav Andrey (Praha) MSC: 93D21 PDFBibTeX XMLCite \textit{J. Reyes-Reyes} et al., Math. Probl. Eng. 6, No. 1, 61--83 (2000; Zbl 0988.93073) Full Text: DOI EuDML