Literature

Papers the engine and its metrics build on, grouped by topic.

Layered drawing

• Sugiyama, Tagawa, Toda. Methods for Visual Understanding of Hierarchical System Structures. IEEE Trans. SMC 11(2), 1981. https://doi.org/10.1109/TSMC.1981.4308636. The layered method.
• Gansner, Koutsofios, North, Vo. A Technique for Drawing Directed Graphs. IEEE TSE 19(3), 1993. https://doi.org/10.1109/32.221135. Network-simplex ranking and coordinates, median ordering (dot).
• Brandes, Köpf. Fast and Simple Horizontal Coordinate Assignment. GD 2001. https://doi.org/10.1007/3-540-45848-4_3, with the erratum by Brandes, Walter, Zink, https://arxiv.org/abs/2008.01252. The coordinate fallback and the fast effort.
• Eiglsperger, Siebenhaller, Kaufmann. An Efficient Implementation of Sugiyama's Algorithm for Layered Graph Drawing. JGAA 9(3), 2005. https://doi.org/10.7155/jgaa.00111.
• Forster. A Fast and Simple Heuristic for Constrained Two-Level Crossing Reduction. GD 2004. https://doi.org/10.1007/978-3-540-31843-9_22. Ordering with groups and lanes.
• Schulze, Spönemann, von Hanxleden. Drawing layered graphs with port constraints. JVLC 25(2), 2014. https://doi.org/10.1016/j.jvlc.2013.11.005. Port sides and hints.
• Rüegg, Schulze, Carstens, von Hanxleden. Size- and Port-Aware Horizontal Node Coordinate Assignment. GD 2015. https://doi.org/10.1007/978-3-319-27261-0_12.
• Rüegg, von Hanxleden. Wrapping Layered Graphs. Diagrams 2018. https://doi.org/10.1007/978-3-319-91376-6_72. Row wrapping.
• Wybrow, Marriott, Stuckey. Orthogonal Connector Routing. GD 2009. https://doi.org/10.1007/978-3-642-11805-0_22.
• Kieffer, Dwyer, Marriott, Wybrow. HOLA: Human-like Orthogonal Network Layout. IEEE TVCG 22(1), 2016. https://doi.org/10.1109/TVCG.2015.2467451.
• Domrös, von Hanxleden, Spönemann, Rüegg, et al. The Eclipse Layout Kernel. arXiv:2311.00533. https://arxiv.org/abs/2311.00533. ELK, one of the engines in the benchmarks.

Labels

• Kakoulis, Tollis. An Algorithm for Labeling Edges of Hierarchical Drawings. GD 1997. https://doi.org/10.1007/3-540-63938-1_60.
• Schulze, Wechselberg, von Hanxleden. Edge Label Placement in Layered Graph Drawing. Diagrams 2018. https://doi.org/10.1007/978-3-319-91376-6_10. Labels as layer members.
• Schulze, Lasch, von Hanxleden. Label management: Keeping complex diagrams usable. VL/HCC 2016. https://doi.org/10.1109/VLHCC.2016.7739657.

Trees

• Buchheim, Jünger, Leipert. Improving Walker's Algorithm to Run in Linear Time. GD 2002. https://doi.org/10.1007/3-540-36151-0_32. The tidy-tree layout.

Process models

• van der Aalst, Berti. Discovering Object-centric Petri Nets. Fundamenta Informaticae 175, 2020. https://doi.org/10.3233/FI-2020-1946.
• Brachmann, Koren, Liß, van der Aalst. Visualizing Object-Centric Petri Nets. BPM 2025 Workshops. https://doi.org/10.1007/978-3-032-13426-4_43.
• Lee, Song, van der Aalst. Layouting Object-Centric Directly Follows Graphs. BPM Forum 2025. https://doi.org/10.1007/978-3-032-02929-4_12.
• van der Aalst. A practitioner's guide to process mining: Limitations of the directly-follows graph. Procedia CS 164, 2019. https://doi.org/10.1016/j.procs.2019.12.189.
• Mennens, Scheepens, Westenberg. A stable graph layout algorithm for processes. Computer Graphics Forum 38(3), 2019. https://doi.org/10.1111/cgf.13723.
• Gschwind, Pinggera, Zugal, Reijers, Weber. A linear time layout algorithm for business process models. JVLC 25(2), 2014. https://doi.org/10.1016/j.jvlc.2013.11.002.
• Kitzmann, König, Lübke, Singer. A Simple Algorithm for Automatic Layout of BPMN Processes. IEEE CEC 2009. https://doi.org/10.1109/CEC.2009.28.
• Albrecht, Effinger, Held, Kaufmann. An automatic layout algorithm for BPEL processes. SOFTVIS 2010. https://doi.org/10.1145/1879211.1879237.
• Effinger, Jogsch, Seiz. On a Study of Layout Aesthetics for Business Process Models Using BPMN. BPMN 2010. https://doi.org/10.1007/978-3-642-16298-5_5.
• Vanhatalo, Völzer, Koehler. The Refined Process Structure Tree. Data & Knowledge Engineering 68(9), 2009. https://doi.org/10.1016/j.datak.2009.02.015. Fork/join blocks.
• Mendling, Reijers, van der Aalst. Seven process modeling guidelines (7PMG). Information and Software Technology 52(2), 2010. https://doi.org/10.1016/j.infsof.2009.08.004.

Readability and metrics

• Purchase. Which aesthetic has the greatest effect on human understanding? GD 1997. https://doi.org/10.1007/3-540-63938-1_67, and Metrics for Graph Drawing Aesthetics. JVLC 13(5), 2002. https://doi.org/10.1006/jvlc.2002.0232.
• Ware, Purchase, Colpoys, McGill. Cognitive Measurements of Graph Aesthetics. Information Visualization 1(2), 2002. https://doi.org/10.1057/palgrave.ivs.9500013.
• Huang, Hong, Eades. Effects of Crossing Angles. PacificVis 2008. https://doi.org/10.1109/PACIFICVIS.2008.4475457.
• Huang, Eades, Hong. Measuring Effectiveness of Graph Visualizations: A Cognitive Load Perspective. Information Visualization 8(3), 2009. https://doi.org/10.1057/ivs.2009.10.
• Mooney, Purchase, Wybrow, Kobourov. The Multi-Dimensional Landscape of Graph Drawing Metrics. PacificVis 2024. https://doi.org/10.1109/PacificVis60374.2024.00022.
• Dunne, Shneiderman. Improving graph drawing readability by incorporating readability metrics. HCIL-2009-13, University of Maryland, 2009.
• Bennett, Ryall, Spalteholz, Gooch. The Aesthetics of Graph Visualization. Computational Aesthetics 2007. https://doi.org/10.2312/COMPAESTH/COMPAESTH07/057-064.
• Burattin, Bernstein, Neurauter, Soffer, Weber. Detection and quantification of flow consistency in business process models. SoSyM 17, 2018. https://doi.org/10.1007/s10270-017-0576-y.
• Bernstein, Soffer. Identifying and Quantifying Visual Layout Features of Business Process Models. BPMDS/EMMSAD 2015. https://doi.org/10.1007/978-3-319-19237-6_13.
• Lübke, Ahrens, Schneider. Influence of diagram layout and scrolling on understandability of BPMN processes. Information Technology and Management 22(2), 2021. https://doi.org/10.1007/s10799-021-00327-7.
• Petrusel, Mendling. Eye-Tracking the Factors of Process Model Comprehension Tasks. CAiSE 2013. https://doi.org/10.1007/978-3-642-38709-8_15.
• Schrepfer, Wolf, Mendling, Reijers. The Impact of Secondary Notation on Process Model Understanding. PoEM 2009. https://doi.org/10.1007/978-3-642-05352-8_13.
• Figl, Strembeck. On the Importance of Flow Direction in Business Process Models. ICSOFT-EA 2014. https://doi.org/10.5220/0005090401320136.
• Xu, Rooney, Passmore, Ham, Nguyen. A User Study on Curved Edges in Graph Visualization. IEEE TVCG 18(12), 2012. https://doi.org/10.1109/TVCG.2012.189.
• McGee, Dingliana. An empirical study on the impact of edge bundling on user comprehension of graphs. AVI 2012. https://doi.org/10.1145/2254556.2254670.

Stability

• Misue, Eades, Lai, Sugiyama. Layout Adjustment and the Mental Map. JVLC 6(2), 1995. https://doi.org/10.1006/jvlc.1995.1010.
• Purchase, Hoggan, Görg. How Important Is the "Mental Map"? GD 2006. https://doi.org/10.1007/978-3-540-70904-6_19.
• Archambault, Purchase. The "Map" in the mental map: Experimental results in dynamic graph drawing. IJHCS 71(11), 2013. https://doi.org/10.1016/j.ijhcs.2013.08.004.
• Diehl, Görg. Graphs, They Are Changing. GD 2002. https://doi.org/10.1007/3-540-36151-0_3.
• Häge, Rehse. Mental Maps in Process Mining: Does Stabilizing DFGs Improve Process Analysis Performance? BPM 2025. https://doi.org/10.1007/978-3-032-02867-9_31.