@inproceedings{NiemuellerReuterFerreinetal.2016, author = {Niemueller, Tim and Reuter, Sebastian and Ferrein, Alexander and Jeschke, Sabina and Lakemeyer, Gerhard}, title = {Evaluation of the RoboCup Logistics League and Derived Criteria for Future Competitions}, series = {RoboCup 2015: Robot World Cup XIX}, booktitle = {RoboCup 2015: Robot World Cup XIX}, editor = {Almeida, Luis}, publisher = {Springer International Publishing}, address = {Cham}, isbn = {978-3-319-29339-4}, doi = {10.1007/978-3-319-29339-4_3}, pages = {31 -- 43}, year = {2016}, language = {en} } @inproceedings{NiemuellerNeumannHenkeetal.2017, author = {Niemueller, Tim and Neumann, Tobias and Henke, Christoph and Sch{\"o}nitz, Sebastian and Reuter, Sebastian and Ferrein, Alexander and Jeschke, Sabina and Lakemeyer, Gerhard}, title = {Improvements for a robust production in the RoboCup logistics league 2016}, series = {RoboCup 2016: Robot World Cup XX. RoboCup 2016.}, booktitle = {RoboCup 2016: Robot World Cup XX. RoboCup 2016.}, publisher = {Springer}, address = {Cham}, isbn = {978-3-319-68792-6}, doi = {10.1007/978-3-319-68792-6_49}, pages = {589 -- 600}, year = {2017}, language = {en} } @inproceedings{HofmannLimpertMatareetal.2019, author = {Hofmann, Till and Limpert, Nicolas and Matar{\´e}, Victor and Ferrein, Alexander and Lakemeyer, Gerhard}, title = {Winning the RoboCup Logistics League with Fast Navigation, Precise Manipulation, and Robust Goal Reasoning}, series = {RoboCup 2019: Robot World Cup XXIII. RoboCup}, booktitle = {RoboCup 2019: Robot World Cup XXIII. RoboCup}, publisher = {Springer}, address = {Cham}, isbn = {978-3-030-35699-6}, doi = {10.1007/978-3-030-35699-6_41}, pages = {504 -- 516}, year = {2019}, language = {en} } @inproceedings{FerreinNiemuellerSchifferetal.2013, author = {Ferrein, Alexander and Niem{\"u}ller, Tim and Schiffer, Stefan and Lakemeyer, Gerhard}, title = {Lessons learnt from developing the embodied AI platform CAESAR for domestic service robotics}, series = {Designing intelligent robots : reintegrating AI II ; papers from the AAAI spring symposium ; [held March 25 - 27, 2013 in Palo Alto, California, USA, on the campus of Stanford University]. (Technical Report / Association for the Advancement of Artificial Intelligence ; 2013,4)}, booktitle = {Designing intelligent robots : reintegrating AI II ; papers from the AAAI spring symposium ; [held March 25 - 27, 2013 in Palo Alto, California, USA, on the campus of Stanford University]. (Technical Report / Association for the Advancement of Artificial Intelligence ; 2013,4)}, editor = {Boots, Byron}, organization = {American Association for Artificial Intelligence}, isbn = {9781577356011}, pages = {21 -- 26}, year = {2013}, language = {en} } @inproceedings{LeingartnerMaurerSteinbaueretal.2013, author = {Leingartner, Max and Maurer, Johannes and Steinbauer, Gerald and Ferrein, Alexander}, title = {Evaluation of sensors and mapping approaches for disasters in tunnels}, series = {IEEE International Symposium on Safety, Security, and Rescue Robotics : SSRR : 21-26 Oct. 2013, Linkoping, Sweden}, booktitle = {IEEE International Symposium on Safety, Security, and Rescue Robotics : SSRR : 21-26 Oct. 2013, Linkoping, Sweden}, organization = {Institute of Electrical and Electronics Engineers}, isbn = {978-1-4799-0879-0}, pages = {1 -- 7}, year = {2013}, language = {en} } @inproceedings{NiemuellerEwertReuteretal.2013, author = {Niem{\"u}ller, Tim and Ewert, Daniel and Reuter, Sebastian and Ferrein, Alexander and Jeschke, Sabina and Lakemeyer, Gerhard}, title = {The Carologistics RoboCup Logistics Team 2013}, series = {RoboCup 2013 : Eindhoven}, booktitle = {RoboCup 2013 : Eindhoven}, organization = {Robocup <2013, Eindhoven>}, pages = {1 -- 8}, year = {2013}, language = {en} } @inproceedings{FerreinLakemeyerSchiffer2006, author = {Ferrein, Alexander and Lakemeyer, Gerhard and Schiffer, Stefan}, title = {AllemaniACs@ home 2006 team description}, pages = {1 -- 6}, year = {2006}, language = {en} } @inproceedings{HofmannMatareNeumannetal.2018, author = {Hofmann, Till and Matar{\´e}, Victor and Neumann, Tobias and Sch{\"o}nitz, Sebastian and Henke, Christoph and Limpert, Nicolas and Niemueller, Tim and Ferrein, Alexander and Jeschke, Sabina and Lakemeyer, Gerhard}, title = {Enhancing Software and Hardware Reliability for a Successful Participation in the RoboCup Logistics League 2017}, publisher = {Springer}, address = {Cham}, isbn = {978-3-030-00308-1}, doi = {10.1007/978-3-030-00308-1_40}, pages = {486 -- 497}, year = {2018}, language = {en} } @inproceedings{Ferrein2015, author = {Ferrein, Alexander}, title = {3D-Mapping von Straßentunneln}, series = {16. Geokinematischer Tag, 07. und 08. Mai 2015 : Tagungsband / Technische Universit{\"a}t Bergakademie Freiberg}, booktitle = {16. Geokinematischer Tag, 07. und 08. Mai 2015 : Tagungsband / Technische Universit{\"a}t Bergakademie Freiberg}, pages = {31 -- 40}, year = {2015}, language = {de} } @inproceedings{ArndtConzenElsenetal.2023, author = {Arndt, Tobias and Conzen, Max and Elsen, Ingo and Ferrein, Alexander and Galla, Oskar and K{\"o}se, Hakan and Schiffer, Stefan and Tschesche, Matteo}, title = {Anomaly detection in the metal-textile industry for the reduction of the cognitive load of quality control workers}, series = {PETRA '23: Proceedings of the 16th International Conference on PErvasive Technologies Related to Assistive Environments}, booktitle = {PETRA '23: Proceedings of the 16th International Conference on PErvasive Technologies Related to Assistive Environments}, publisher = {ACM}, isbn = {9798400700699}, doi = {10.1145/3594806.3596558}, pages = {535 -- 542}, year = {2023}, abstract = {This paper presents an approach for reducing the cognitive load for humans working in quality control (QC) for production processes that adhere to the 6σ -methodology. While 100\% QC requires every part to be inspected, this task can be reduced when a human-in-the-loop QC process gets supported by an anomaly detection system that only presents those parts for manual inspection that have a significant likelihood of being defective. This approach shows good results when applied to image-based QC for metal textile products.}, language = {en} } @inproceedings{AlhwarinFerreinScholl2019, author = {Alhwarin, Faraj and Ferrein, Alexander and Scholl, Ingrid}, title = {An Efficient Hashing Algorithm for NN Problem in HD Spaces}, series = {Lecture Notes in Computer Science}, booktitle = {Lecture Notes in Computer Science}, isbn = {978-303005498-4}, doi = {10.1007/978-3-030-05499-1_6}, pages = {101 -- 115}, year = {2019}, language = {en} } @inproceedings{NiemuellerLakemeyerFerrein2013, author = {Niem{\"u}ller, Tim and Lakemeyer, Gerhard and Ferrein, Alexander}, title = {Aspects of integrating diverse software into robotic systems extended abstract}, series = {ICRA 2013 - 8th Workshop on Software Development and Integration in Robotics (SDIR), Karlsruhe, Germany}, booktitle = {ICRA 2013 - 8th Workshop on Software Development and Integration in Robotics (SDIR), Karlsruhe, Germany}, pages = {1 -- 2}, year = {2013}, language = {en} } @inproceedings{AlhwarinFerreinScholl2018, author = {Alhwarin, Faraj and Ferrein, Alexander and Scholl, Ingrid}, title = {CRVM: Circular Random Variable-based Matcher - A Novel Hashing Method for Fast NN Search in High-dimensional Spaces}, series = {Proceedings of the 7th International Conference on Pattern Recognition Applications and Methods, ICPRAM 2018}, booktitle = {Proceedings of the 7th International Conference on Pattern Recognition Applications and Methods, ICPRAM 2018}, isbn = {978-989-758-276-9}, doi = {10.5220/0006692802140221}, pages = {214 -- 221}, year = {2018}, language = {en} } @inproceedings{AlhwarinSchifferFerreinetal.2018, author = {Alhwarin, Faraj and Schiffer, Stefan and Ferrein, Alexander and Scholl, Ingrid}, title = {Optimized KinectFusion Algorithm for 3D Scanning Applications}, series = {Proceedings of the 11th International Joint Conference on Biomedical Engineering Systems and Technologies - Volume 2: BIOIMAGING}, booktitle = {Proceedings of the 11th International Joint Conference on Biomedical Engineering Systems and Technologies - Volume 2: BIOIMAGING}, isbn = {978-989-758-278-3}, doi = {10.5220/0006594700500057}, pages = {50 -- 57}, year = {2018}, language = {en} } @inproceedings{Ferrein2015, author = {Ferrein, Alexander}, title = {Robots: challenges, chances and risks for solving 21st century problems}, series = {President's Invitation Lecture / South African Institute of Electrical Engineers : May 21 \& 22, 2015, University of Johannesburg}, booktitle = {President's Invitation Lecture / South African Institute of Electrical Engineers : May 21 \& 22, 2015, University of Johannesburg}, organization = {South African Institute of Electrical Engineers}, pages = {1 -- 45}, year = {2015}, language = {en} } @inproceedings{FerreinSchifferKallweit2018, author = {Ferrein, Alexander and Schiffer, Stefan and Kallweit, Stephan}, title = {The ROSIN Education Concept - Fostering ROS Industrial-Related Robotics Education in Europe}, series = {ROBOT 2017: Third Iberian Robotics Conference}, booktitle = {ROBOT 2017: Third Iberian Robotics Conference}, publisher = {Springer}, address = {Cham}, isbn = {978-3-319-70836-2}, doi = {10.1007/978-3-319-70836-2_31}, pages = {370 -- 381}, year = {2018}, language = {en} } @inproceedings{NiemuellerNeumannHenkeetal.2017, author = {Niemueller, Tim and Neumann, Tobias and Henke, Christoph and Sch{\"o}nitz, Sebastian and Reuter, Sebastian and Ferrein, Alexander and Jeschke, Sabina and Lakemeyer, Gerhard}, title = {International Harting Open Source Award 2016: Fawkes for the RoboCup Logistics League}, series = {RoboCup 2016: RoboCup 2016: Robot World Cup XX. RoboCup 2016}, booktitle = {RoboCup 2016: RoboCup 2016: Robot World Cup XX. RoboCup 2016}, publisher = {Springer}, address = {Cham}, isbn = {978-3-319-68792-6}, doi = {10.1007/978-3-319-68792-6_53}, pages = {634 -- 642}, year = {2017}, language = {en} } @inproceedings{KrueckelNoldenFerreinetal.2015, author = {Kr{\"u}ckel, Kai and Nolden, Florian and Ferrein, Alexander and Scholl, Ingrid}, title = {Intuitive visual teleoperation for UGVs using free-look augmented reality displays}, series = {2015 IEEE International Conference on Robotics and Automation (ICRA), Seattle, WA}, booktitle = {2015 IEEE International Conference on Robotics and Automation (ICRA), Seattle, WA}, doi = {10.1109/ICRA.2015.7139809}, pages = {4412 -- 4417}, year = {2015}, language = {en} } @inproceedings{NeumannDuelbergSchifferetal.2016, author = {Neumann, Tobias and D{\"u}lberg, Enno and Schiffer, Stefan and Ferrein, Alexander}, title = {A rotating platform for swift acquisition of dense 3D point clouds}, series = {Intelligent Robotics and Applications: 9th International Conference, ICIRA 2016, Tokyo, Japan, August 22-24, 2016, Proceedings, Part I}, volume = {9834}, booktitle = {Intelligent Robotics and Applications: 9th International Conference, ICIRA 2016, Tokyo, Japan, August 22-24, 2016, Proceedings, Part I}, publisher = {Springer}, isbn = {978-3-319-43505-3 (Print)}, doi = {10.1007/978-3-319-43506-0_22}, pages = {257 -- 268}, year = {2016}, language = {en} } @inproceedings{NeumannFerreinKallweitetal.2014, author = {Neumann, Tobias and Ferrein, Alexander and Kallweit, Stephan and Scholl, Ingrid}, title = {Towards a mobile mapping robot for underground mines}, series = {7th Conference of Robotics and Mechatronics : RobMech 2014 : 27th and 28th Nov. 2014, Cape Town}, booktitle = {7th Conference of Robotics and Mechatronics : RobMech 2014 : 27th and 28th Nov. 2014, Cape Town}, organization = {Conference of Robotics and Mechatronics <7, 2014, Cape Town, South Africa>}, pages = {1 -- 6}, year = {2014}, language = {en} } @inproceedings{KallweitFerreinScholletal.2014, author = {Kallweit, Stephan and Ferrein, Alexander and Scholl, Ingrid and Reichert, Walter}, title = {Mobile Autonome Systeme in der Lehre, am Beispiel der ROS Summer School}, series = {Tagungsband AALE 2014 : das Forum f{\"u}r Fachleute der Automatisierungstechnik aus Hochschulen und Wirtschaft ; 11. Fachkonferenz, Regensburg ; [11. Konferenz f{\"u}r Angewandte Automatisierungstechnik in Lehre und Entwicklung / Ostbayerische Technische Hochschule Regensburg; VFAALE, Verein der Freunde und F{\"o}rderer der Angewandten Automatisierungstechnik]}, booktitle = {Tagungsband AALE 2014 : das Forum f{\"u}r Fachleute der Automatisierungstechnik aus Hochschulen und Wirtschaft ; 11. Fachkonferenz, Regensburg ; [11. Konferenz f{\"u}r Angewandte Automatisierungstechnik in Lehre und Entwicklung / Ostbayerische Technische Hochschule Regensburg; VFAALE, Verein der Freunde und F{\"o}rderer der Angewandten Automatisierungstechnik]}, publisher = {Dt. Industrieverl.}, address = {M{\"u}nchen}, isbn = {978-3-8356-7142-3}, pages = {157 -- 163}, year = {2014}, language = {de} } @inproceedings{EltesterFerreinSchiffer2020, author = {Eltester, Niklas Sebastian and Ferrein, Alexander and Schiffer, Stefan}, title = {A smart factory setup based on the RoboCup logistics league}, series = {2020 IEEE Conference on Industrial Cyberphysical Systems (ICPS)}, booktitle = {2020 IEEE Conference on Industrial Cyberphysical Systems (ICPS)}, publisher = {IEEE}, address = {New York, NY}, doi = {10.1109/ICPS48405.2020.9274766}, pages = {297 -- 302}, year = {2020}, abstract = {In this paper we present SMART-FACTORY, a setup for a research and teaching facility in industrial robotics that is based on the RoboCup Logistics League. It is driven by the need for developing and applying solutions for digital production. Digitization receives constantly increasing attention in many areas, especially in industry. The common theme is to make things smart by using intelligent computer technology. Especially in the last decade there have been many attempts to improve existing processes in factories, for example, in production logistics, also with deploying cyber-physical systems. An initiative that explores challenges and opportunities for robots in such a setting is the RoboCup Logistics League. Since its foundation in 2012 it is an international effort for research and education in an intra-warehouse logistics scenario. During seven years of competition a lot of knowledge and experience regarding autonomous robots was gained. This knowledge and experience shall provide the basis for further research in challenges of future production. The focus of our SMART-FACTORY is to create a stimulating environment for research on logistics robotics, for teaching activities in computer science and electrical engineering programmes as well as for industrial users to study and explore the feasibility of future technologies. Building on a very successful history in the RoboCup Logistics League we aim to provide stakeholders with a dedicated facility oriented at their individual needs.}, language = {en} } @inproceedings{FerreinPotgieterSteinbauer2009, author = {Ferrein, Alexander and Potgieter, Anet and Steinbauer, Gerald}, title = {Self-aware robots - What do we need from learning, deliberation, and reactive control?}, series = {HYCAS 2009 : International Workshop on Hybrid Control of Autonomous Systems : Integrating Learning, Deliberation and Reactive Control : Pasadena, Calif., 13 July 2009}, booktitle = {HYCAS 2009 : International Workshop on Hybrid Control of Autonomous Systems : Integrating Learning, Deliberation and Reactive Control : Pasadena, Calif., 13 July 2009}, publisher = {AAAI Pr.}, pages = {1 -- 5}, year = {2009}, language = {en} } @inproceedings{SteinbauerFerrein2019, author = {Steinbauer, Gerald and Ferrein, Alexander}, title = {CogRob 2018 : Cognitive Robotics Workshop. Proceedings of the 11th Cognitive Robotics Workshop 2018 co-located with 16th International Conference on Principles of Knowledge Representation and Reasoning (KR 2018). Tempe, AZ, USA, October 27th, 2018.}, series = {CEUR workshop proceedings}, booktitle = {CEUR workshop proceedings}, number = {Vol-2325}, issn = {1613-0073}, pages = {46 Seiten}, year = {2019}, language = {en} } @inproceedings{DonnerRabelScholletal.2019, author = {Donner, Ralf and Rabel, Matthias and Scholl, Ingrid and Ferrein, Alexander and Donner, Marc and Geier, Andreas and John, Andr{\´e} and K{\"o}hler, Christian and Varga, Sebastian}, title = {Die Extraktion bergbaulich relevanter Merkmale aus 3D-Punktwolken eines untertagetauglichen mobilen Multisensorsystems}, series = {Tagungsband Geomonitoring}, booktitle = {Tagungsband Geomonitoring}, doi = {10.15488/4515}, pages = {91 -- 110}, year = {2019}, language = {de} } @inproceedings{FerreinBharatheeshaSchifferetal.2019, author = {Ferrein, Alexander and Bharatheesha, Mukunda and Schiffer, Stefan and Corbato, Carlos Hernandez}, title = {TRROS 2018 : Teaching Robotics with ROS Workshop at ERF 2018; Proceedings of the Workshop on Teaching Robotics with ROS (held at ERF 2018), co-located with European Robotics Forum 2018 (ERF 2018), Tampere, Finland, March 15th, 2018}, series = {CEUR Workshop Proceedings}, booktitle = {CEUR Workshop Proceedings}, number = {Vol-2329}, issn = {1613-0073}, pages = {68 Seiten}, year = {2019}, language = {en} } @inproceedings{FerreinSchollNeumannetal.2019, author = {Ferrein, Alexander and Scholl, Ingrid and Neumann, Tobias and Kr{\"u}ckel, Kai and Schiffer, Stefan}, title = {A system for continuous underground site mapping and exploration}, doi = {10.5772/intechopen.85859}, pages = {16 Seiten}, year = {2019}, language = {en} } @inproceedings{MarcoFerrein2017, author = {Marco, Heather G. and Ferrein, Alexander}, title = {AGNES: The African-German Network of Excellence in Science}, series = {Proceedings of the 2nd Developing World Robotics Forum, Workshop at IEEE AFRICON 2017}, booktitle = {Proceedings of the 2nd Developing World Robotics Forum, Workshop at IEEE AFRICON 2017}, pages = {1 -- 2}, year = {2017}, language = {en} } @inproceedings{FerreinKallweitLautermann2012, author = {Ferrein, Alexander and Kallweit, Stephan and Lautermann, Mark}, title = {Towards an autonomous pilot system for a tunnel boring machine}, series = {5th Robotics and Mechatronics Conference of South Africa (ROBMECH) : 26 - 27 November 2012 ; CSIR International Conference Centre Gauteng South Africa}, booktitle = {5th Robotics and Mechatronics Conference of South Africa (ROBMECH) : 26 - 27 November 2012 ; CSIR International Conference Centre Gauteng South Africa}, publisher = {IEEE}, address = {Piscataway, NJ}, isbn = {978-1-4673-5183-6}, year = {2012}, language = {en} } @inproceedings{ChajanSchulteTiggesRekeetal.2021, author = {Chajan, Eduard and Schulte-Tigges, Joschua and Reke, Michael and Ferrein, Alexander and Matheis, Dominik and Walter, Thomas}, title = {GPU based model-predictive path control for self-driving vehicles}, series = {IEEE Intelligent Vehicles Symposium (IV)}, booktitle = {IEEE Intelligent Vehicles Symposium (IV)}, publisher = {IEEE}, address = {New York, NY}, isbn = {978-1-7281-5394-0}, doi = {10.1109/IV48863.2021.9575619}, pages = {1243 -- 1248}, year = {2021}, abstract = {One central challenge for self-driving cars is a proper path-planning. Once a trajectory has been found, the next challenge is to accurately and safely follow the precalculated path. The model-predictive controller (MPC) is a common approach for the lateral control of autonomous vehicles. The MPC uses a vehicle dynamics model to predict the future states of the vehicle for a given prediction horizon. However, in order to achieve real-time path control, the computational load is usually large, which leads to short prediction horizons. To deal with the computational load, the control algorithm can be parallelized on the graphics processing unit (GPU). In contrast to the widely used stochastic methods, in this paper we propose a deterministic approach based on grid search. Our approach focuses on systematically discovering the search area with different levels of granularity. To achieve this, we split the optimization algorithm into multiple iterations. The best sequence of each iteration is then used as an initial solution to the next iteration. The granularity increases, resulting in smooth and predictable steering angle sequences. We present a novel GPU-based algorithm and show its accuracy and realtime abilities with a number of real-world experiments.}, language = {en} } @inproceedings{RekePeterSchulteTiggesetal.2020, author = {Reke, Michael and Peter, Daniel and Schulte-Tigges, Joschua and Schiffer, Stefan and Ferrein, Alexander and Walter, Thomas and Matheis, Dominik}, title = {A Self-Driving Car Architecture in ROS2}, series = {2020 International SAUPEC/RobMech/PRASA Conference, Cape Town, South Africa}, booktitle = {2020 International SAUPEC/RobMech/PRASA Conference, Cape Town, South Africa}, publisher = {IEEE}, address = {New York, NY}, isbn = {978-1-7281-4162-6}, doi = {10.1109/SAUPEC/RobMech/PRASA48453.2020.9041020}, pages = {1 -- 6}, year = {2020}, abstract = {In this paper we report on an architecture for a self-driving car that is based on ROS2. Self-driving cars have to take decisions based on their sensory input in real-time, providing high reliability with a strong demand in functional safety. In principle, self-driving cars are robots. However, typical robot software, in general, and the previous version of the Robot Operating System (ROS), in particular, does not always meet these requirements. With the successor ROS2 the situation has changed and it might be considered as a solution for automated and autonomous driving. Existing robotic software based on ROS was not ready for safety critical applications like self-driving cars. We propose an architecture for using ROS2 for a self-driving car that enables safe and reliable real-time behaviour, but keeping the advantages of ROS such as a distributed architecture and standardised message types. First experiments with an automated real passenger car at lower and higher speed-levels show that our approach seems feasible for autonomous driving under the necessary real-time conditions.}, language = {en} } @inproceedings{SchifferFerreinLakemeyer2011, author = {Schiffer, Stefan and Ferrein, Alexander and Lakemeyer, Gerhard}, title = {Fuzzy representations and control for domestic service robots in Golog}, series = {Intelligent robotics and applications : 4th International conference, ICIRA 2011, Aachen, Germany, December 6-8, 2011, proceedings, part I. (Lecture notes in computer science ; 7102)}, booktitle = {Intelligent robotics and applications : 4th International conference, ICIRA 2011, Aachen, Germany, December 6-8, 2011, proceedings, part I. (Lecture notes in computer science ; 7102)}, publisher = {ACM}, address = {New York}, isbn = {978-3-642-25486-4}, doi = {10.1007/978-3-642-25489-5_24}, pages = {241 -- 250}, year = {2011}, abstract = {In the RoboCup@Home domestic service robot competition, complex tasks such as "get the cup from the kitchen and bring it to the living room" or "find me this and that object in the apartment" have to be accomplished. At these competitions the robots may only be instructed by natural language. As humans use qualitative concepts such as "near" or "far", the robot needs to cope with them, too. For our domestic robot, we use the robot programming and plan language Readylog, our variant of Golog. In previous work we extended the action language Golog, which was developed for the high-level control of agents and robots, with fuzzy concepts and showed how to embed fuzzy controllers in Golog. In this paper, we demonstrate how these notions can be fruitfully applied to two domestic service robotic scenarios. In the first application, we demonstrate how qualitative fluents based on a fuzzy set semantics can be deployed. In the second program, we show an example of a fuzzy controller for a follow-a-person task.}, language = {en} }