Research interests Graph algorithms and graph theory Combinatorial optimization Computational complexity Coauthors Luitpold Babel, Daniel Bayer, Andreas Brandstädt David B. Chandler, Maw-Shang Chang, Chi-Yeh Chen Mitre C. Dourado, Feodor F. Dragan Babak Farzad, Carl Feghali, Jiri Fiala Petr Golovach, Martin C. Golumbic Peter L. Hammer, Chinh T. Hoang, Stefan Hougardy, Sun-Yuan Hsieh Klaus Jansen, Felix Joos Ton Kloks, Christian Komusiewicz, Dieter Kratsch, Stefan Kratsch Lap Chi Lau, Hoang-Oanh Le, Marina Lipshteyn, Vadim V. Lozin Suhail Mahfud, Raffaele Mosca, Haiko Müller Ragnar Nevries, Ngoc Tuy Nguyen (Nguyễn Ngọc Túy) Stephan Olariu, Andrea Oversberg Sheng-Lung Peng, Florian Pfender, Thomas Podelleck, Erich Prisner, Fábio Protti Bert Randerath, Dieter Rautenbach, Ernst de Ridder, Christian Rosenke Eike Seidel, Oliver Schaudt, Ingo Schiermeyer, Jerry Spinrad, R. Sritharan, Jayme L. Szwarcfiter, Thomas Szymczak Jan Arne Telle, Zsolt Tuza Ryuhei Uehara Annegret Wagler Articles in Refereed Journals Other (Articles in Refereed Conferences etc.) On polynomial kernelization for Stable Cutset Stefan Kratsch, Van Bang Le Discrete Applied Mathematics 383 (2026) 184-202; doi: 10.1016/j.dam.2025.12.026 The parameterized complexity of Strong Conflict-Free Vertex-Connection Colorability Carl Feghali, Hoang-Oanh Le, Van Bang Le Discrete Applied Mathematics 383 (2026) 85-93; doi: 10.1016/j.dam.2025.12.025 Complexity and algorithms for matching cut problems in graphs without long induced paths and cycles Hoang-Oanh Le, Van Bang Le Journal of Computer and System Sciences 156 (2026) 103723; doi: 10.1016/j.jcss.2025.103723 Computing Optimal Leaf Roots of Chordal Cographs in Linear Time Van Bang Le, Christian Rosenke Journal of Graph Algorithms and Applications 28 (2024) 243-274; doi: 10.7155/jgaa.v28i1.2942 Complexity of the (Connected) Cluster Vertex Deletion problem on H-free graphs Hoang-Oanh Le, Van Bang Le Theory of Computing Systems 68 (2024) 250-270; doi: 10.1007/s00224-024-10161-3 On the d-Claw Vertex Deletion Problem Sun-Yuan Hsieh, Hoang-Oanh Le, Van Bang Le, Sheng-Lung Peng Algorithmica 86 (2024) 505-525; doi: 10.1007/s00453-023-01144-w The Perfect Matching Cut Revisited Van Bang Le, Jan Arne Telle Theoretical Computer Science 931 (2022) 117-130; doi: 10.1016/j.tcs.2022.07.035 Refined Notions of Parameterized Enumeration Kernels with Applications to Matching Cut Enumeration Petr Golovach, Christian Komusiewicz, Dieter Kratsch, Van Bang Le Journal of Computer and System Sciences 123 (2022) 76-102; doi: 10.1016/j.jcss.2021.07.005. Matching Cut in graphs with large minimum degree Chi-Yeh Chen, Sun-Yuan Hsieh, Hoang-Oanh Le, Van Bang Le, Sheng-Lung Peng Algorithmica 83 (2021) 1238-1255; doi: 10.1007/s00453-020-00782-8 Color-line and proper color-line graphs Van Bang Le, Florian Pfender Discrete Applied Mathematics 278 (2020) 73-82; doi:10.1016/j.dam.2019.06.002; pdf Matching Cut: Kernelization, single-exponential FPT, and exact exponential algorithms Christian Komusiewicz, Dieter Kratsch, Van Bang Le Discrete Applied Mathematics 283 (2020) 44-58; doi:10.1016/j.dam.2019.12.010; pdf Hardness and structural results for half-squares of restricted tree convex bipartite graphs Hoang-Oanh Le, Van Bang Le Algorithmica 81 (2019) 4258-4274. doi:10.1007/s00453-018-0440-7 Map graphs having witnesses of large girth Hoang-Oanh Le, Van Bang Le Theoretical Computer Science 772 (2019) 143-148. doi:10.1016/j.tcs.2018.12.010; arXiv A complexity dichotomy for Matching Cut in (bipartite) graphs of fixed diameter Hoang-Oanh Le, Van Bang Le Theoretical Computer Science 770 (2019) 69-78. doi:10.1016/j.tcs.2018.10.029; arXiv On the Complete Width and Edge Clique Cover problems Van Bang Le, Sheng-Lung Peng Journal of Combinatorial Optimization 36 (2018) 532-548. DOI: 10.1007/s10878-016-0106-9; arXiv Good characterizations and linear time recognition for 2-probe block graphs Van Bang Le, Sheng-Lung Peng Discrete Applied Mathematics 231 (2017) 181-189. DOI: 10.1016/j.dam.2016.11.015; arXiv Characterization and recognition of some opposition and coalition graph classes Van Bang Le, Thomas Podelleck Discrete Applied Mathematics 216 (2017) 261-272. doi:10.1016/j.dam.2015.06.007. pdf (arXiv version) A unified approach to recognize squares of split graphs Van Bang Le, Andrea Oversberg, Oliver Schaudt Theoretical Computer Science 648 (2016) 26-33. doi:10.1016/j.tcs.2016.07.037. pdf (arXiv version) Algorithms solving the Matching Cut problem Dieter Kratsch, Van Bang Le Theoretical Computer Science 609 (2016) 328-335. doi:10.1016/j.tcs.2015.10.016 Polynomial time recognition of squares of ptolemaic graphs and 3-sun-free split graphs Van Bang Le, Andrea Oversberg, Oliver Schaudt Theoretical Computer Science 602 (2015) 39-49. doi:10.1016/j.tcs.2015.07.060. pdf (arXiv version) Characterizing and recognizing probe block graphs Van Bang Le, Sheng-Lung Peng Theoretical Computer Science 568 (2015) 97-102. doi:10.1016/j.tcs.2014.12.014 Forests and trees among Gallai graphs Felix Joos, Van Bang Le, Dieter Rautenbach Discrete Mathematics 338 (2015) 190-195. doi:10.1016/j.disc.2014.09.003 Complexity and algorithms for recognizing polar and monopolar graphs Van Bang Le, Ragnar Nevries Theoretical Computer Science 528 (2014) 1-11. doi:10.1016/j.tcs.2014.01.032 A note on efficient domination in a superclass of P5-free graphs A. Brandstädt, Van Bang Le Information Processing Letters 114 (2014) 357-359. doi:10.1016/j.ipl.2014.02.007 On opposition graphs, coalition graphs, and bipartite permutation graphs Van Bang Le Discrete Applied Mathematics 168 (2014) 26-33. doi:10.1016/j.dam.2012.11.020 Complexity results for rainbow matchings Van Bang Le, Florian Pfender Theoretical Computer Science 524 (2014) 27-33. doi:10.1016/j.tcs.2013.12.013. pdf (arXiv version) Integral mixed unit interval graphs Van Bang Le, Dieter Rautenbach Discrete Applied Mathematics 161 (2013) 1028-1036. doi:10.1016/j.dam.2012.09.013 Extremal graphs having no stable cutsets Van Bang Le, Florian Pfender The Electronic Journal of Combinatorics 20 (2013). #P35 Mixed unit interval graphs Mitre C. Dourado, Van Bang Le, Fábio Protti, Dieter Rautenbach, Jayme L. Szwarcfiter Discrete Mathematics 312 (2012) 3357-3363. doi:10.1016/j.disc.2012.07.037 Complexity of finding graph roots with girth conditions Babak Farzad, Lap Chi Lau, Van Bang Le and Nguyen Ngoc Tuy Algorithmica 62 (2012) 38-53. DOI: 10.1007/s00453-010-9442-9. pdf (arXiv version) Path-bicolorable graphs A. Brandstädt, Martin C. Golumbic, Van Bang Le, Marina Lipshteyn Graphs and Combinatorics 27 (2011) 799-819. DOI: 10.1007/s00373-010-1007-9 A good characterization of squares of strongly chordal split graphs Van Bang Le, Nguyen Ngoc Tuy Information Processing Letters 111 (2011) 120-123. doi:10.1016/j.ipl.2010.11.003 Two characterizations of chain partitioned probe graphs Van Bang Le Annals of Operations Research 188 (2011) 279-283. DOI: 10.1007/s10479-010-0749-3 Exact leaf powers A. Brandstädt, Van Bang Le, Dieter Rautenbach Theoretical Computer Science 411 (2010) 2968-2977. dx.doi.org/10.1016/j.tcs.2010.04.027 The square of a block graph Van Bang Le, Nguyen Ngoc Tuy Discrete Mathematics 310 (2010) 734-741. pdf Simplicial powers of graphs A. Brandstädt, Van Bang Le Theoretical Computer Science 410 (2009) 5443-5454. pdf Probe threshold and probe trivially perfect graphs Daniel Bayer, Van Bang Le, H.N. (Ernst) de Ridder Theoretical Computer Science 410 (2009) 4812-4822. pdf A forbidden induced subgraph characterization of distance-hereditary 5-leaf powers A. Brandstädt, Van Bang Le, Dieter Rautenbach Discrete Math. 309 (2009) 3843-3852. pdf Structure and linear time recognition of 4-leaf powers A. Brandstädt, Van Bang Le, R. Sritharan ACM Transactions on Algorithms 5 (2008). Article No. 11 (pdf) On Stable cutsets in claw-free graphs and planar graphs Van Bang Le, Raffaele Mosca, Haiko Müller J. Discrete Algorithms 6 (2008) 256-276. pdf On the complexity of 4-coloring graphs without long induced paths Van Bang Le, Bert Randerath, Ingo Schiermeyer Theoretical Computer Science 389 (1-2) (2007) 330-335. pdf The subchromatic index of graphs Jiri Fiala, Van Bang Le Tatra Mountain Mathematical Publications 36 (2007) 129-146. pdf Probe split graphs Van Bang Le, Ernst de Ridder Discrete Mathematics and Theoretical Computer Science 9 (2007) 207-238. pdf Tree spanners for bipartite graphs and probe interval graphs A. Brandstädt, Feodor Dragan, Hoang-Oanh Le, Van Bang Le, Ryuhei Uehara Algorithmica 47 (2007) 27-51. DOI:10.1007/s00453-006-1209-y New Applications of the clique separator decomposition for the Maximum Weight Stable Set problem A. Brandstädt, Van Bang Le, Suhail Mahfud Theoretical Computer Science 370 (2007) 229-239. pdf Structure and linear time recognition of 3-leaf powers A. Brandstädt, Van Bang Le Information Processing Letters 98 (2006) 133-138. pdf Bisplit graphs A. Brandstädt, Peter L. Hammer, Van Bang Le, Vadim V. Lozin Discrete Mathematics 299 (1-3) (2005) 11-32. pdf Consequences of an algorithm for bridged graphs Van Bang Le, Jeremy P. Spinrad Discrete Mathematics 280 (1-3) (2004) 271-274. pdf Split-perfect graphs: Characterizations and algorithmic use A. Brandstädt, Van Bang Le SIAM J. Discrete Mathematics 17 (3) (2004) 341-360. pdf Efficient robust algorithms for the Maximum Weight Stable Set problem in chair-free graph classes A. Brandstädt, Van Bang Le, H.N. de Ridder Information Processing Letters 89 (4) (2004) 165-173. pdf Tree spanners on chordal graphs: Complexity and algorithms A. Brandstädt, Feodor Dragan, Hoang-Oanh Le, Van Bang Le Theoretical Computer Science 310 (1-3) (2004) 329-354. pdf Stability number of bull- and chair-free graphs revisited A. Brandstädt, Chinh T. Hoang, Van Bang Le Discrete Applied Mathematics 131 (1) (2003) 39-50. pdf Splitting a graph into disjoint induced paths or cycles Hoang-Oanh Le, Van Bang Le, Haiko Müller Discrete Applied Mathematics 131 (1) (2003) 199-212. pdf Graph subcolorings: complexity and algorithms Jiri Fiala, Klaus Jansen, Van Bang Le, Eike Seidel SIAM J. Discrete Mathematics 16 (4) (2003) 635-650. pdf Bipartite-perfect graphs Van Bang Le Discrete Applied Mathematics 127 (3) (2003) 581-599. On stable cutsets in line graphs Van Bang Le, Bert Randerath Theoretical Computer Science 301 (1-3) (2003) 463-475. pdf Recognizing the P4-structure of claw-free graphs and a larger graph class Luitpold Babel, A. Brandstädt, Van Bang Le Discrete Mathematics and Theoretical Computer Science 5 (1) (2002) 127-146. (electronic) On alpha-redundant vertices in P5-free graphs A. Brandstädt, Hoang-Oanh Le, Van Bang Le Information Processing Letters 82 (3) (2002) 119-122. The NP-completeness of (1,r)-subcolorability of cubic graphs Hoang-Oanh Le, Van Bang Le Information Processing Letters 81 (3) (2002) 157-162. P4-free colorings and P4-bipartite graphs Chinh T. Hoang, Van Bang Le Discrete Mathematics and Theoretical Computer Science 4 (2) (2001) 109-122. (electronic) Efficiently recognizing the P4-structure of trees and of bipartite graphs without short cycles A. Brandstädt, Van Bang Le, Stephan Olariu Graphs and Combinatorics 16 (4) (2000) 381-387. On stable cut-sets in graphs A. Brandstädt, Feodor Dragan, Van Bang Le, Thomas Szymczak Discrete Applied Mathematics 105 (2000) 39-50. pdf Some conjectures on perfect graphs Van Bang Le Discussiones Mathematicae Graph Theory 20 (2000) 155-159. Recognizing perfect 2-split graphs Chinh T. Hoang, Van Bang Le SIAM J. Discrete Mathematics 13 (2000) 48-55. On P4-transversals of perfect graphs Chinh T. Hoang, Van Bang Le Discrete Mathematics 216 (2000) 195-210. Recognizing the P4-structure of block graphs A. Brandstädt, Van Bang Le Discrete Applied Mathematics 99 (1-3) (2000) 349-366. Recognizing the P4-structure of bipartite graphs Luitpold Babel, A. Brandstädt, Van Bang Le Discrete Applied Mathematics 93 (2-3) (1999) 157-168. A Good characterization of cograph contractions Van Bang Le J. Graph Theory 30 (1999) 309-318. pdf Optimal tree 3-spanners in directed path graphs Hoang-Oanh Le, Van Bang Le Networks 34 (2) (1999) 81-87. pdf. Erratum Tree- and forest-perfect graphs A. Brandstädt, Van Bang Le Discrete Applied Mathematics 95 (1-3) (1999) 141-162. The complexity of some problems related to Graph 3-Colorability A. Brandstädt, Van Bang Le, Thomas Szymczak Discrete Applied Mathematics 89 (1-3) (1998) 59-73. pdf Duchet-type theorems for powers of HHD-free graphs A. Brandstädt, Van Bang Le, Thomas Szymczak Discrete Mathematics 177 (1997) 9-16. Wing-triangulated graphs are perfect Stefan Hougardy, Van Bang Le, Annegret Wagler J. Graph Theory 24 (1997) 25-31. Gallai graphs and anti-Gallai graphs Van Bang Le Discrete Mathematics 159 (1996) 179-189. pdf Cycle-perfect graphs are perfect Van Bang Le J. Graph Theory 23 (1996) 351-353. Iterated k-line graphs Van Bang Le, Erich Prisner Graphs and Combinatorics 10 (1994) 193-203. Perfect k-line graphs and k-total graphs Van Bang Le J. Graph Theory 17 (1993) 65-73. Mortality of iterated Gallai graphs Van Bang Le Periodica Mathematica Hungarica 27 (1993) 105-124. pdf On inverse problems of the cycle graph operator Van Bang Le, Erich Prisner Graphs and Combinatorics 8 (1992) 155-164. Accepted/To appear Articles in Refereed Journals Other (Articles in Refereed Conferences etc.) The complexity of strong conflict-free vertex-connection k-colorability Sun-Yuan Hsieh, Hoang-Oanh Le, Van Bang Le, Sheng-Lung Peng 30th International Computing and Combinatorics Conference (COCOON 2024); LNCS 15161, arXiv On polynomial kernelization for Stable Cutset Stefan Kratsch, Van Bang Le 50th International Workshop on Graph-Theoretic Concepts in Computer Science (WG 2024); LNCS 1476, arXiv Computing Optimal Leaf Roots of Chordal Cographs in Linear Time Van Bang Le, Christian Rosenke 24th International Symposium on Fundamentals of Computation Theory (FCT 2023); pdf Complexity resuls for matching cut problems in graphs without long induced paths Hoang-Oanh Le, Van Bang Le The 49th International Workshop on Graph-Theoretic Concepts in Computer Science (WG 2023); pdf Complexity of the Cluster Vertex Deletion problem on H-free graphs Hoang-Oanh Le, Van Bang Le 47th International Symposium on Mathematical Foundations of Computer Science (MFCS 2022); pdf On the d-Claw Vertex Deletion Problem Sun-Yuan Hsieh, Van Bang Le, Sheng-Lung Peng The 27th International Computing and Combinatorics Conference (COCOON 2021); pdf Leaf powers Christian Rosenke, Van Bang Le, A. Brandstädt A chapter in Topics in Algorithmic Graph Theory, Cambridge University Press (2021), edited by Lowell W. Beineke, Martin Charles Golumbic, Robin J. Wilson. The Perfect Matching Cut Problem Revisited Van Bang Le, Jan Arne Telle The 47th International Workshop on Graph-Theoretic Concepts in Computer Science (WG 2021); pdf Refined Notions of Parameterized Enumeration Kernels with Applications to Matching Cut Enumeration Petr Golovach, Christian Komusiewicz, Dieter Kratsch, Van Bang Le The 38th International Symposium on Theoretical Aspects of Computer Science (STACS 2021); pdf Constrained representations of map graphs and half-squares Hoang-Oanh Le, Van Bang Le 44th International Symposium on Mathematical Foundations of Computer Science (MFCS 2019); pdf Matching Cut in graphs with large minimum degree Sun-Yuan Hsieh, Hoang-Oanh Le, Van Bang Le, Sheng-Lung Peng 25th International Computing and Combinatorics Conference (COCOON 2019); pdf Matching Cut: Kernelization, single-exponential FPT, and exact exponential algorithms Christian Komusiewicz, Dieter Kratsch, Van Bang Le 13th International Symposium on Parameterized and Exact Computation (IPEC 2018); pdf Hardness and structural results for half-squares of restricted tree convex bipartite graphs Hoang-Oanh Le, Van Bang Le 23rd International Computing and Combinatorics Conference (COCOON 2017), Lecture Notes in Computer Science 10392 (2017) 359-370. DOI: 10.1007/978-3-319-62389-4_30 On the complexity of Matching Cut in graphs of fixed diameter Hoang-Oanh Le, Van Bang Le 27th International Symposium on Algorithms and Computation (ISAAC 2016); pdf Extended version: arXiv Algorithms solving the Matching Cut problem Dieter Kratsch, Van Bang Le 9th International Conference on Algorithms and Complexity (CIAC 2015), Lecture Notes in Computer Science 9079 (2015) 288-299. DOI: 10.1007/978-3-319-18173-8_2 On the Complete Width and Edge Clique Cover problems Van Bang Le, Sheng-Lung Peng 21st Annual International Computing and Combinatorics Conference (COCOON 2015), Lecture Notes in Computer Science 9198 (2015) 537-547. DOI: 10.1007/978-3-319-21398-9_42 Good characterizations and linear time recognition for 2-probe block graphs Van Bang Le, Sheng-Lung Peng International Computer Symposium ICS 2014. doi:10.3233/978-1-61499-484-8-22 Polynomial time recognition of squares of ptolemaic graphs and 3-sun-free split graphs Van Bang Le, Andrea Oversberg, Oliver Schaudt WG 2014, Lecture Notes in Computer Science 8747 (2014) 360-371. DOI: 10.1007/978-3-319-12340-0 30 Characterizing and recognizing probe block graphs Van Bang Le, Sheng-Lung Peng ICS 2012, Smart Innovation, Systems and Technologies 20 (2013) 7-13. doi: 10.1007/978-3-642-35452-6_2 Integral mixed unit interval graphs Van Bang Le, Dieter Rautenbach COCOON 2012, Lecture Notes in Computer Science 7434 (2012) 495-506. doi:10.1007/978-3-642-32241-9_42 (pdf) Recognizing polar planar graphs using new results for monopolarity Van Bang Le, Ragnar Nevries ISAAC 2011, Lecture Notes in Computer Science 7074 (2011) 120-129. pdf Hardness results and efficient algorithms for graph powers Van Bang Le, Ngoc Tuy Nguyen WG 2009, Lecture Notes in Computer Science 5911 (2010) 238-249. pdf Finding optimal rainbow connection is hard Van Bang Le, Zsolt Tuza Preprints CS-03-09, Univ. Rostock, Institut für Informatik, 2009. pdf Computing graph roots without short cycles Babak Farzad, Lap Chi Lau, Van Bang Le, Ngoc Tuy Nguyen STACS 2009, pdf Path-bicolorable graphs A. Brandstädt, M.C. Golumbic, Van Bang Le, M. Lipshteyn Lecture Notes in Computer Science 5420 (2009) 172-182 (Golumbic Festschrift). pdf Simplicial powers of graphs A. Brandstädt, Van Bang Le COCOA 2008, Lecture Notes in Computer Science 5165 (2008) 160-170. pdf Probe ptolemaic graphs David B. Chandler, Maw-Shang Chang, Ton Kloks, Van Bang Le, Sheng-Lung Peng COCOON 2008, Lecture Notes in Computer Science 5092 (2008) 468-477. pdf Characterisations and linear-time recognition of probe cographs Van Bang Le, H.N. (Ernst) de Ridder WG 2007, Lecture Notes in Computer Science 4769 (2007) 226-237. pdf New applications of the clique separator decomposition for the Maximum Weight Stable Set problem A. Brandstädt, Van Bang Le, Suhail Mahfud FCT 2005, Lecture Notes in Computer Science 3623 (2005) 516-527. pdf On stable cutsets in claw-free graphs and planar graphs Van Bang Le, Raffaele Mosca, Haiko Müller WG 2005, Lecture Notes in Computer Science 3787 (2005) 163-174. pdf Tree spanners for bipartite graphs and probe interval graphs A. Brandstädt, Feodor Dragan, Hoang-Oanh Le, Van Bang Le, Ryuhei Uehara WG 2003, Lecture Notes in Computer Science 2880 (2003) 106-118. pdf Tree spanners on chordal graphs: Complexity, algorithms, open problems A. Brandstädt, Feodor Dragan, Hoang-Oanh Le, Van Bang Le ISAAC 2002, Lecture Notes in Computer Science 2518 (2002) 163-174. Graph subcolorings: Complexity and algorithms Jiri Fiala, Klaus Jansen, Van Bang Le, Eike Seidel WG 2001, Lecture Notes in Computer Science 2204 (2001) 154-165. On stable cutsets in line graphs Van Bang Le, Bert Randerath WG 2001,Lecture Notes in Computer Science 2204 (2001) 263-271. Split-perfect Graphs: Characterizations and algorithmic use A. Brandstädt, Van Bang Le WG 2000, Lecture Notes in Computer Science 1928 (2000) 71-82. Linear-time recognition of the P4-structure of trees A. Brandstädt, Van Bang Le, Stephan Olariu Rutcor Research Report RRR 19-96, Rutgers University, 1996. Induced cycles and odd powers of graphs Andreas Brandstädt, Feodor F. Dragan, Van Bang Le Universität Rostock, FB Informatik, 1995. Preprint CS-09-95 P4-Structure in Special Graphs: Algorithms and Perfection Van Bang Le Habilitationsschrift, FB Informatik, Universität Rostock, 1999. Gallai-Graphs and Their Iteration Behavior Van Bang Le Dissertation, FB Mathematik, Technische Universität Berlin, 1994. Facet graphs of pure simplical complexes and related concepts Van Bang Le, Erich Prisner Universität Hamburg, Preprint No. 19, 1992. pdf Forcing graphs and forbidden subgraphs Van Bang Le Technische Universität Berlin, Preprint No. 281, 1991. Transitive Kantenforcierung und perfekte Graphen Van Bang Le Diplomarbeit, FB Mathematik, Technische Universität Berlin, 1988. Books & Editing Graph Classes: A Survey A. Brandstädt, Van Bang Le, Jeremy P. Spinrad SIAM, Philadelphia, 1999. Proceedings of the 27th International Workshop on Graph-Theoretic Concepts in Computer Science (WG 2001) A. Brandstädt, Van Bang Le (Eds.) Lecture Notes in Computer Science, Vol. 2204, Springer, 2001. Proceedings of the 3rd conference on Optimal Discrete Structures and Algorithms (ODSA 2006) A. Brandstädt, Konrad Engel, Hans-Dietrich Gronau, Van Bang Le (Eds.) Discrete Applied Mathematics 157 (9) (2009). Proceedings of the 4th conference on Optimal Discrete Structures and Algorithms (ODSA 2010) A. Brandstädt, Konrad Engel, Hans-Dietrich Gronau, Roger Labahn, Van Bang Le, Florian Pfender (Eds.) Discrete Applied Mathematics 163 (2014). Special Issue To Andreas Brandstädt Feodor F. Dragan, Dieter Kratsch, Van Bang Le (Eds.) Discrete Applied Mathematics 216, Part 1, (2017).   Van Bang Le