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Steven Kelk
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2020 – today
- 2025
- [j48]Steven Chaplick, Martin Frohn, Steven Kelk, Johann Lottermoser, Matús Mihalák:
Approximation ratio of the min-degree greedy algorithm for Maximum Independent Set on interval and chordal graphs. Discret. Appl. Math. 360: 275-281 (2025) - 2024
- [j47]Steven Kelk, Simone Linz, Ruben Meuwese:
Deep kernelization for the Tree Bisection and Reconnection (TBR) distance in phylogenetics. J. Comput. Syst. Sci. 142: 103519 (2024) - [j46]Steven Kelk, Ruben Meuwese, Stephan Wagner:
Convex Characters, Algorithms, and Matchings. SIAM J. Discret. Math. 38(1): 380-411 (2024) - [j45]Steven Kelk, Ruben Meuwese:
Agreement forests of caterpillar trees: Complexity, kernelization and branching. Theor. Comput. Sci. 1003: 114608 (2024) - [c14]Virginia Ardévol Martínez, Steven Chaplick, Steven Kelk, Ruben Meuwese, Matús Mihalák, Georgios Stamoulis:
Relaxed Agreement Forests. SOFSEM 2024: 40-54 - [i40]Steven Chaplick, Martin Frohn, Steven Kelk, Johann Lottermoser, Matús Mihalák:
Approximation Ratio of the Min-Degree Greedy Algorithm for Maximum Independent Set on Interval and Chordal Graphs. CoRR abs/2403.10868 (2024) - [i39]Martin Frohn, Niels Holtgrefe, Leo van Iersel, Mark Jones, Steven Kelk:
Reconstructing semi-directed level-1 networks using few quarnets. CoRR abs/2409.06034 (2024) - [i38]David Mestel, Steven Chaplick, Steven Kelk, Ruben Meuwese:
Split-or-decompose: Improved FPT branching algorithms for maximum agreement forests. CoRR abs/2409.18634 (2024) - [i37]Martin Frohn, Steven Kelk, Simona Vychytilova:
A branch-&-price approach to the unrooted maximum agreement forest problem. CoRR abs/2410.04122 (2024) - 2023
- [j44]Steven Kelk, Simone Linz, Ruben Meuwese:
Cyclic generators and an improved linear kernel for the rooted subtree prune and regraft distance. Inf. Process. Lett. 180: 106336 (2023) - [j43]Miguel Bosch Calvo, Steven Kelk:
An improved kernel for the flip distance problem on simple convex polygons. Inf. Process. Lett. 182: 106381 (2023) - [c13]Steven Chaplick, Steven Kelk, Ruben Meuwese, Matús Mihalák, Georgios Stamoulis:
Snakes and Ladders: A Treewidth Story. WG 2023: 187-200 - [i36]Steven Chaplick, Steven Kelk, Ruben Meuwese, Matús Mihalák, Georgios Stamoulis:
Snakes and Ladders: a Treewidth Story. CoRR abs/2302.10662 (2023) - [i35]Steven Kelk, Ruben Meuwese:
Agreement forests of caterpillar trees: complexity, kernelization and branching. CoRR abs/2307.12176 (2023) - [i34]Virginia Aardevol Martinez, Steven Chaplick, Steven Kelk, Ruben Meuwese, Matús Mihalák, Georgios Stamoulis:
Relaxed Agreement Forests. CoRR abs/2309.01110 (2023) - 2022
- [j42]Sander Borst, Leo van Iersel, Mark Jones, Steven Kelk:
New FPT Algorithms for Finding the Temporal Hybridization Number for Sets of Phylogenetic Trees. Algorithmica 84(7): 2050-2087 (2022) - [j41]Rim van Wersch, Steven Kelk, Simone Linz, Georgios Stamoulis:
Reflections on kernelizing and computing unrooted agreement forests. Ann. Oper. Res. 309(1): 425-451 (2022) - [j40]Steven Kelk, Ruben Meuwese:
Sharp Upper and Lower Bounds on a Restricted Class of Convex Characters. Electron. J. Comb. 29(1) (2022) - [i33]Steven Kelk, Simone Linz, Ruben Meuwese:
Cyclic generators and an improved linear kernel for the rooted subtree prune and regraft distance. CoRR abs/2202.09904 (2022) - [i32]Steven Kelk, Simone Linz, Ruben Meuwese:
Deep kernelization for the Tree Bisection and Reconnnect (TBR) distance in phylogenetics. CoRR abs/2206.04451 (2022) - 2021
- [j39]Mark Jones, Steven Kelk, Leen Stougie:
Maximum parsimony distance on phylogenetic trees: A linear kernel and constant factor approximation algorithm. J. Comput. Syst. Sci. 117: 165-181 (2021) - [c12]Miguel Bosch Calvo, Steven Kelk:
An Improved Kernel for the Flip Distance Problem on Simple Convex Polygons. CCCG 2021: 195-199 - 2020
- [i31]Mark Jones, Steven Kelk, Leen Stougie:
Maximum parsimony distance on phylogenetictrees: a linear kernel and constant factor approximation algorithm. CoRR abs/2004.02298 (2020) - [i30]Sander Borst, Leo van Iersel, Mark Jones, Steven Kelk:
New FPT algorithms for finding the temporal hybridization number for sets of phylogenetic trees. CoRR abs/2007.13615 (2020) - [i29]Rim van Wersch, Steven Kelk, Simone Linz, Georgios Stamoulis:
Reflections on kernelizing and computing unrooted agreement forests. CoRR abs/2012.07354 (2020)
2010 – 2019
- 2019
- [j38]Borislav Slavchev, Evelina Masliankova, Steven Kelk:
A Machine Learning Approach to Algorithm Selection for Exact Computation of Treewidth. Algorithms 12(10): 200 (2019) - [j37]Janosch Döcker, Leo van Iersel, Steven Kelk, Simone Linz:
Deciding the existence of a cherry-picking sequence is hard on two trees. Discret. Appl. Math. 260: 131-143 (2019) - [j36]Steven Kelk, Georgios Stamoulis:
Integrality gaps for colorful matchings. Discret. Optim. 32: 73-92 (2019) - [j35]Remie Janssen, Mark Jones, Steven Kelk, Georgios Stamoulis, Taoyang Wu:
Treewidth of display graphs: bounds, brambles and applications. J. Graph Algorithms Appl. 23(4): 715-743 (2019) - [j34]Steven Kelk, Simone Linz:
A Tight Kernel for Computing the Tree Bisection and Reconnection Distance between Two Phylogenetic Trees. SIAM J. Discret. Math. 33(3): 1556-1574 (2019) - [i28]Ricards Marcinkevics, Steven Kelk, Carlo Galuzzi, Berthold Stegemann:
Discovery of Important Subsequences in Electrocardiogram Beats Using the Nearest Neighbour Algorithm. CoRR abs/1901.09187 (2019) - [i27]Steven Kelk, Simone Linz:
New reduction rules for the tree bisection and reconnection distance. CoRR abs/1905.01468 (2019) - [i26]Cameron Browne, Dennis J. N. J. Soemers, Éric Piette, Matthew Stephenson, Michael Conrad, Walter Crist, Thierry Depaulis, Eddie Duggan, Fred Horn, Steven Kelk, Simon M. Lucas, João Pedro Neto, David Parlett, Abdallah Saffidine, Ulrich Schädler, Jorge Nuno Silva, Alex de Voogt, Mark H. M. Winands:
Foundations of Digital Archæoludology. CoRR abs/1905.13516 (2019) - [i25]Mark Jones, Philippe Gambette, Leo van Iersel, Remie Janssen, Steven Kelk, Fabio Pardi, Céline Scornavacca:
Cutting an alignment with Ockham's razor. CoRR abs/1910.11041 (2019) - 2018
- [j33]Leo van Iersel, Steven Kelk, Georgios Stamoulis, Leen Stougie, Olivier Boes:
On Unrooted and Root-Uncertain Variants of Several Well-Known Phylogenetic Network Problems. Algorithmica 80(11): 2993-3022 (2018) - [j32]Steven Kelk, Georgios Stamoulis, Taoyang Wu:
Treewidth distance on phylogenetic trees. Theor. Comput. Sci. 731: 99-117 (2018) - [c11]Axel Goblet, Steven Kelk, Matús Mihalák, Georgios Stamoulis:
On a Fixed Haplotype Variant of the Minimum Error Correction Problem. COCOON 2018: 554-566 - [i24]Steven Kelk, Georgios Stamoulis:
Integrality Gaps for Bounded Color Matchings. CoRR abs/1801.07937 (2018) - [i23]Leo van Iersel, Mark Jones, Steven Kelk:
A third strike against perfect phylogeny. CoRR abs/1804.07232 (2018) - [i22]Remie Janssen, Mark Jones, Steven Kelk, Georgios Stamoulis, Taoyang Wu:
Treewidth of display graphs: bounds, brambles and applications. CoRR abs/1809.00907 (2018) - [i21]Steven Kelk, Simone Linz:
A tight kernel for computing the tree bisection and reconnection distance between two phylogenetic trees. CoRR abs/1811.06892 (2018) - 2017
- [j31]Steven Kelk, Georgios Stamoulis:
A note on convex characters, Fibonacci numbers and exponential-time algorithms. Adv. Appl. Math. 84: 34-46 (2017) - [j30]Rim van Wersch, Steven Kelk:
ToTo: An open database for computation, storage and retrieval of tree decompositions. Discret. Appl. Math. 217: 389-393 (2017) - [j29]Julia Matsieva, Steven Kelk, Céline Scornavacca, Chris Whidden, Dan Gusfield:
A Resolution of the Static Formulation Question for the Problem of Computing the History Bound. IEEE ACM Trans. Comput. Biol. Bioinform. 14(2): 404-417 (2017) - [j28]Olivier Boes, Mareike Fischer, Steven Kelk:
A Linear Bound on the Number of States in Optimal Convex Characters for Maximum Parsimony Distance. IEEE ACM Trans. Comput. Biol. Bioinform. 14(2): 472-477 (2017) - [c10]Fabian Braun, Olivier Caelen, Evgueni N. Smirnov, Steven Kelk, Bertrand Lebichot:
Improving Card Fraud Detection Through Suspicious Pattern Discovery. IEA/AIE (2) 2017: 181-190 - [i20]Steven Kelk, Georgios Stamoulis, Taoyang Wu:
Treewidth distance on phylogenetic trees. CoRR abs/1703.10840 (2017) - [i19]Steven Kelk, Fabio Pardi, Céline Scornavacca, Leo van Iersel:
Finding the most parsimonious or likely tree in a network with respect to an alignment. CoRR abs/1707.03648 (2017) - [i18]Janosch Döcker, Leo van Iersel, Steven Kelk, Simone Linz:
Deciding the existence of a cherry-picking sequence is hard on two trees. CoRR abs/1712.02965 (2017) - 2016
- [j27]Leo van Iersel, Steven Kelk, Céline Scornavacca:
Kernelizations for the hybridization number problem on multiple nonbinary trees. J. Comput. Syst. Sci. 82(6): 1075-1089 (2016) - [j26]Steven Kelk, Leo van Iersel, Céline Scornavacca, Mathias Weller:
Phylogenetic incongruence through the lens of Monadic Second Order logic. J. Graph Algorithms Appl. 20(2): 189-215 (2016) - [j25]Leo van Iersel, Steven Kelk, Nela Lekic, Chris Whidden, Norbert Zeh:
Hybridization Number on Three Rooted Binary Trees is EPT. SIAM J. Discret. Math. 30(3): 1607-1631 (2016) - [j24]Steven Kelk:
Review of ReCombinatorics: The Algorithmics of Ancestral Recombination Graphs and Explicit Phylogenetic Networks by Dan Gusfield. SIGACT News 47(1): 12-15 (2016) - [j23]Steven Kelk:
Review of: Genome-Scale Algorithm Design (Biological sequence analysis in the era of high-throughput sequencing) by Veli Mäkinen, Djamal Belazzougui, Fabio Cunial and Alexandru I. Tomescu. SIGACT News 47(3): 15-18 (2016) - [j22]Leo van Iersel, Steven Kelk, Nela Lekic, Simone Linz:
Satisfying ternary permutation constraints by multiple linear orders or phylogenetic trees. Theor. Comput. Sci. 609: 1-21 (2016) - [j21]Steven Kelk, Mareike Fischer, Vincent Moulton, Taoyang Wu:
Reduction rules for the maximum parsimony distance on phylogenetic trees. Theor. Comput. Sci. 646: 1-15 (2016) - [i17]Philippe Gambette, Leo van Iersel, Steven Kelk, Fabio Pardi, Céline Scornavacca:
Do branch lengths help to locate a tree in a phylogenetic network? CoRR abs/1607.06285 (2016) - [i16]Leo van Iersel, Steven Kelk, Georgios Stamoulis, Leen Stougie, Olivier Boes:
On unrooted and root-uncertain variants of several well-known phylogenetic network problems. CoRR abs/1609.00544 (2016) - 2015
- [j20]Alexander Grigoriev, Steven Kelk, Nela Lekic:
On Low Treewidth Graphs and Supertrees. J. Graph Algorithms Appl. 19(1): 325-343 (2015) - [j19]Mareike Fischer, Leo van Iersel, Steven Kelk, Céline Scornavacca:
On Computing the Maximum Parsimony Score of a Phylogenetic Network. SIAM J. Discret. Math. 29(1): 559-585 (2015) - [i15]Steven Kelk, Leo van Iersel, Céline Scornavacca:
Phylogenetic incongruence through the lens of Monadic Second Order logic. CoRR abs/1503.00368 (2015) - [i14]Olivier Boes, Mareike Fischer, Steven Kelk:
A linear bound on the number of states in optimal convex characters for maximum parsimony distance. CoRR abs/1506.06404 (2015) - [i13]Steven Kelk:
A note on convex characters and Fibonacci numbers. CoRR abs/1508.02598 (2015) - [i12]Steven Kelk, Mareike Fischer, Vincent Moulton, Taoyang Wu:
Reduction rules for the maximum parsimony distance on phylogenetic trees. CoRR abs/1512.07459 (2015) - 2014
- [j18]Steven Kelk, Céline Scornavacca:
Constructing Minimal Phylogenetic Networks from Softwired Clusters is Fixed Parameter Tractable. Algorithmica 68(4): 886-915 (2014) - [j17]Leo van Iersel, Steven Kelk, Nela Lekic, Céline Scornavacca:
A practical approximation algorithm for solving massive instances of hybridization number for binary and nonbinary trees. BMC Bioinform. 15: 127 (2014) - [j16]Céline Scornavacca, Leo van Iersel, Steven Kelk, David Bryant:
The agreement problem for unrooted phylogenetic trees is FPT. J. Graph Algorithms Appl. 18(3): 385-392 (2014) - [j15]Leo van Iersel, Steven Kelk, Nela Lekic, Leen Stougie:
Approximation Algorithms for Nonbinary Agreement Forests. SIAM J. Discret. Math. 28(1): 49-66 (2014) - [c9]Alexander Grigoriev, Steven Kelk, Nela Lekic:
On Low Treewidth Graphs and Supertrees. AlCoB 2014: 71-82 - [c8]Leo van Iersel, Steven Kelk:
Kernelizations for the Hybridization Number Problem on Multiple Nonbinary Trees. WG 2014: 299-311 - [i11]Leo van Iersel, Steven Kelk, Nela Lekic, Chris Whidden, Norbert Zeh:
Hybridization Number on Three Trees. CoRR abs/1402.2136 (2014) - [i10]Alexander Grigoriev, Steven Kelk, Nela Lekic:
On low treewidth graphs and supertrees. CoRR abs/1402.7224 (2014) - [i9]Leo van Iersel, Steven Kelk, Nela Lekic, Simone Linz:
Satisfying ternary permutation constraints by multiple linear orders or phylogenetic trees. CoRR abs/1410.2371 (2014) - [i8]Steven Kelk, Mareike Fischer:
On the complexity of computing MP distance between binary phylogenetic trees. CoRR abs/1412.4076 (2014) - 2013
- [j14]Teresa Piovesan, Steven Kelk:
A Simple Fixed Parameter Tractable Algorithm for Computing the Hybridization Number of Two (Not Necessarily Binary) Trees. IEEE ACM Trans. Comput. Biol. Bioinform. 10(1): 18-25 (2013) - [i7]Leo van Iersel, Steven Kelk:
Kernelizations for the hybridization number problem on multiple nonbinary trees. CoRR abs/1311.4045 (2013) - 2012
- [j13]Steven Kelk, Leo van Iersel, Nela Lekic, Simone Linz, Céline Scornavacca, Leen Stougie:
Cycle Killer...Qu'est-ce que c'est? On the Comparative Approximability of Hybridization Number and Directed Feedback Vertex Set. SIAM J. Discret. Math. 26(4): 1635-1656 (2012) - [j12]Steven Kelk, Céline Scornavacca, Leo van Iersel:
On the Elusiveness of Clusters. IEEE ACM Trans. Comput. Biol. Bioinform. 9(2): 517-534 (2012) - [c7]Leo van Iersel, Steven Kelk, Nela Lekic, Céline Scornavacca:
A Practical Approximation Algorithm for Solving Massive Instances of Hybridization Number. WABI 2012: 430-440 - [i6]Steven Kelk, Céline Scornavacca:
Towards the fixed parameter tractability of constructing minimal phylogenetic networks from arbitrary sets of nonbinary trees. CoRR abs/1207.7034 (2012) - [i5]Leo van Iersel, Steven Kelk, Nela Lekic, Leen Stougie:
Computing nonbinary agreement forests. CoRR abs/1210.3211 (2012) - 2011
- [j11]Leo van Iersel, Steven Kelk:
Constructing the Simplest Possible Phylogenetic Network from Triplets. Algorithmica 60(2): 207-235 (2011) - [j10]Katharina T. Huber, Leo van Iersel, Steven Kelk, Radoslaw Suchecki:
A Practical Algorithm for Reconstructing Level-1 Phylogenetic Networks. IEEE ACM Trans. Comput. Biol. Bioinform. 8(3): 635-649 (2011) - [j9]Harry Buhrman, Peter T. S. van der Gulik, Steven Kelk, Wouter M. Koolen, Leen Stougie:
Some Mathematical Refinements Concerning Error Minimization in the Genetic Code. IEEE ACM Trans. Comput. Biol. Bioinform. 8(5): 1358-1372 (2011) - [i4]Steven Kelk, Céline Scornavacca, Leo van Iersel:
On the elusiveness of clusters. CoRR abs/1103.1834 (2011) - [i3]Steven Kelk, Céline Scornavacca:
Constructing minimal phylogenetic networks from softwired clusters is fixed parameter tractable. CoRR abs/1108.3653 (2011) - [i2]Steven Kelk:
A note on efficient computation of hybridization number via softwired clusters. CoRR abs/1108.4642 (2011) - [i1]Steven Kelk, Leo van Iersel, Nela Lekic, Simone Linz, Céline Scornavacca, Leen Stougie:
Cycle killer... qu'est-ce que c'est? On the comparative approximability of hybridization number and directed feedback vertex set. CoRR abs/1112.5359 (2011) - 2010
- [j8]Leo van Iersel, Steven Kelk, Regula Rupp, Daniel H. Huson:
Phylogenetic networks do not need to be complex: using fewer reticulations to represent conflicting clusters. Bioinform. 26(12): 124-131 (2010) - [j7]Jaroslaw Byrka, Pawel Gawrychowski, Katharina T. Huber, Steven Kelk:
Worst-case optimal approximation algorithms for maximizing triplet consistency within phylogenetic networks. J. Discrete Algorithms 8(1): 65-75 (2010)
2000 – 2009
- 2009
- [j6]Leo van Iersel, Steven Kelk, Matthias Mnich:
Uniqueness, Intractability and Exact Algorithms: Reflections on Level-k Phylogenetic Networks. J. Bioinform. Comput. Biol. 7(4): 597-623 (2009) - [j5]Leo van Iersel, Judith Keijsper, Steven Kelk, Leen Stougie, Ferry Hagen, Teun Boekhout:
Constructing Level-2 Phylogenetic Networks from Triplets. IEEE ACM Trans. Comput. Biol. Bioinform. 6(4): 667-681 (2009) - 2008
- [j4]Leo van Iersel, Judith Keijsper, Steven Kelk, Leen Stougie:
Shorelines of Islands of Tractability: Algorithms for Parsimony and Minimum Perfect Phylogeny Haplotyping Problems. IEEE ACM Trans. Comput. Biol. Bioinform. 5(2): 301-312 (2008) - [c6]Leo van Iersel, Steven Kelk:
Constructing the Simplest Possible Phylogenetic Network from Triplets. ISAAC 2008: 472-483 - [c5]Leo van Iersel, Judith Keijsper, Steven Kelk, Leen Stougie, Ferry Hagen, Teun Boekhout:
Constructing Level-2 Phylogenetic Networks from Triplets. RECOMB 2008: 450-462 - 2007
- [j3]Rudi Cilibrasi, Leo van Iersel, Steven Kelk, John Tromp:
The Complexity of the Single Individual SNP Haplotyping Problem. Algorithmica 49(1): 13-36 (2007) - [j2]Cor A. J. Hurkens, Leo van Iersel, Judith Keijsper, Steven Kelk, Leen Stougie, John Tromp:
Prefix Reversals on Binary and Ternary Strings. SIAM J. Discret. Math. 21(3): 592-611 (2007) - [c4]Cor A. J. Hurkens, Leo van Iersel, Judith Keijsper, Steven Kelk, Leen Stougie, John Tromp:
Prefix Reversals on Binary and Ternary Strings. AB 2007: 292-306 - 2006
- [c3]Leo van Iersel, Judith Keijsper, Steven Kelk, Leen Stougie:
Beaches of Islands of Tractability: Algorithms for Parsimony and Minimum Perfect Phylogeny Haplotyping Problems. WABI 2006: 80-91 - 2005
- [c2]Rudi Cilibrasi, Leo van Iersel, Steven Kelk, John Tromp:
On the Complexity of Several Haplotyping Problems. WABI 2005: 128-139 - 2004
- [j1]Leslie Ann Goldberg, Steven Kelk, Mike Paterson:
The Complexity of Choosing an H-Coloring (Nearly) Uniformly at Random. SIAM J. Comput. 33(2): 416-432 (2004) - 2003
- [b1]Steven M. Kelk:
On the relative complexity of approximately counting H-colourings. University of Warwick, Coventry, UK, 2003 - 2002
- [c1]Leslie Ann Goldberg, Steven Kelk, Mike Paterson:
The complexity of choosing an H-colouring (nearly) uniformly at random. STOC 2002: 53-62
Coauthor Index
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