@inproceedings{PlatenPoghossianSchoening2006,
  author    = {Platen, J. and Poghossian, Arshak and Sch{\"o}ning, Michael Josef},
  title     = {Pr{\"a}paration von selbstjustierenden Nanostrukturen mittels Schichtausdehnungstechnik},
  series = {Sensoren und Mess-Systeme 2006 : Vortr{\"a}ge der 13. ITG/GMA-Fachtagung vom 13. bis 14.3.2006 in Freiburg/Breisgau},
  booktitle = {Sensoren und Mess-Systeme 2006 : Vortr{\"a}ge der 13. ITG/GMA-Fachtagung vom 13. bis 14.3.2006 in Freiburg/Breisgau},
  publisher = {VDE Verl.},
  address   = {Berlin},
  isbn      = {3-8007-2939-3},
  pages     = {277 -- 280},
  year      = {2006},
  language  = {de}
}
@article{SchoeningPoghossian2006,
  author    = {Sch{\"o}ning, Michael Josef and Poghossian, Arshak},
  title     = {BioFEDs (field-effect devices) : State-of-the-art and new directions},
  series = {Electroanalysis},
  volume    = {18},
  journal   = {Electroanalysis},
  number    = {19-20},
  issn      = {1521-4109},
  doi       = {10.1002/elan.200603609},
  pages     = {1893 -- 1900},
  year      = {2006},
  language  = {en}
}
@article{WuBronderPoghossianetal.2015,
  author    = {Wu, Chunsheng and Bronder, Thomas and Poghossian, Arshak and Werner, Frederik and Sch{\"o}ning, Michael Josef},
  title     = {Label-free detection of DNA using light-addressable potentiometric sensor modified with a positively charged polyelectrolyte layer},
  series = {Nanoscale},
  volume    = {14},
  journal   = {Nanoscale},
  number    = {7},
  publisher = {Royal Society of Chemistry (RSC)},
  address   = {Cambridge},
  doi       = {10.1039/C4NR07225A},
  pages     = {6143 -- 6150},
  year      = {2015},
  abstract  = {A multi-spot (16 spots) light-addressable potentiometric sensor (MLAPS) consisting of an Al-p-Si-SiO2 structure modified with a weak polyelectrolyte layer of PAH (poly(allylamine hydrochloride)) was applied for the label-free electrical detection of DNA (deoxyribonucleic acid) immobilization and hybridization by the intrinsic molecular charge for the first time. To achieve a preferentially flat orientation of DNA strands and thus, to reduce the distance between the DNA charge and MLAPS surface, the negatively charged probe single-stranded DNAs (ssDNA) were electrostatically adsorbed onto the positively charged PAH layer using a simple layer-by-layer (LbL) technique. In this way, more DNA charge can be positioned within the Debye length, yielding a higher sensor signal. The surface potential changes in each spot induced due to the surface modification steps (PAH adsorption, probe ssDNA immobilization, hybridization with complementary target DNA (cDNA), non-specific adsorption of mismatched ssDNA) were determined from the shifts of photocurrent-voltage curves along the voltage axis. A high sensor signal of 83 mV was registered after immobilization of probe ssDNA onto the PAH layer. The hybridization signal increases from 5 mV to 32 mV with increasing the concentration of cDNA from 0.1 nM to 5 μM. In contrast, a small signal of 5 mV was recorded in the case of non-specific adsorption of fully mismatched ssDNA (5 μM). The obtained results demonstrate the potential of the MLAPS in combination with the simple and rapid LbL immobilization technique as a promising platform for the future development of multi-spot light-addressable label-free DNA chips with direct electrical readout.},
  language  = {en}
}
@article{BegingLeinhosJablonskietal.2015,
  author    = {Beging, Stefan and Leinhos, Marcel and Jablonski, Melanie and Poghossian, Arshak and Sch{\"o}ning, Michael Josef},
  title     = {Studying the spatially resolved immobilisation of enzymes on a capacitive field-effect structure by means of nano-spotting},
  series = {Physica status solidi (a)},
  volume    = {212},
  journal   = {Physica status solidi (a)},
  number    = {6},
  publisher = {Wiley},
  address   = {Weinheim},
  issn      = {1862-6319},
  doi       = {10.1002/pssa.201431891},
  pages     = {1353 -- 1358},
  year      = {2015},
  language  = {en}
}
@incollection{PoghossianSchoening2006,
  author    = {Poghossian, Arshak and Sch{\"o}ning, Michael Josef},
  title     = {Silicon-based chemical and biological field-effect sensors},
  series = {Encyclopedia of Sensors. Vol. 9 S - Sk},
  booktitle = {Encyclopedia of Sensors. Vol. 9 S - Sk},
  publisher = {ASP, American Scientific Publ.},
  address   = {Stevenson Ranch, Calif.},
  isbn      = {1-58883-065-9},
  pages     = {463 -- 534},
  year      = {2006},
  language  = {en}
}
@article{PoghossianKatzSchoening2015,
  author    = {Poghossian, Arshak and Katz, Evgeny and Sch{\"o}ning, Michael Josef},
  title     = {Enzyme logic AND-Reset and OR-Reset gates based on a field-effect electronic transducer modified with multi-enzyme membrane},
  series = {Chemical Communications},
  volume    = {51},
  journal   = {Chemical Communications},
  publisher = {Royal Society of Chemistry (RSC)},
  address   = {Cambridge},
  doi       = {10.1039/C5CC01362C},
  pages     = {6564 -- 6567},
  year      = {2015},
  abstract  = {Capacitive field-effect sensors modified with a multi-enzyme membrane have been applied for an electronic transduction of biochemical signals processed by enzyme-based AND-Reset and OR-Reset logic gates. The local pH change at the sensor surface induced by the enzymatic reaction was used for the activation of the Reset function for the first time.},
  language  = {en}
}
@article{HuckPoghossianBaeckeretal.2015,
  author    = {Huck, Christina and Poghossian, Arshak and B{\"a}cker, Matthias and Reisert, Steffen and Kramer, Friederike and Begoyan, Vardges K. and Buniatyan, Vahe V. and Sch{\"o}ning, Michael Josef},
  title     = {Multi-parameter sensing using high-k oxide of barium strontium titanate},
  series = {Physica status solidi (a)},
  volume    = {212},
  journal   = {Physica status solidi (a)},
  number    = {6},
  publisher = {Wiley},
  address   = {Weinheim},
  issn      = {1862-6319},
  doi       = {10.1002/pssa.201431911},
  pages     = {1259},
  year      = {2015},
  abstract  = {High-k perovskite oxide of barium strontium titanate (BST) represents a very attractive multi-functional transducer material for the development of (bio-)chemical sensors. In this work, a Si-based sensor chip containing Pt interdigitated electrodes covered with a thin BST layer (485 nm) has been developed for multi-parameter chemical sensing. The chip has been applied for the contactless measurement of the electrolyte conductivity, the detection of adsorbed charged macromolecules (positively charged polyelectrolytes of polyethylenimine) and the concentration of hydrogen peroxide (H2O2) vapor. The experimental results of functional testing of individual sensors are presented. The mechanism of the BST sensitivity to charged polyelectrolytes and H2O2 vapor has been proposed and discussed.},
  language  = {en}
}
@article{MolinnusBaeckerSiegertetal.2015,
  author    = {Molinnus, Denise and B{\"a}cker, Matthias and Siegert, Petra and Willenberg, H. and Poghossian, Arshak and Keusgen, M. and Sch{\"o}ning, Michael Josef},
  title     = {Detection of Adrenaline Based on Substrate Recycling Amplification},
  series = {Procedia Engineering},
  volume    = {120},
  journal   = {Procedia Engineering},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {1877-7058},
  doi       = {10.1016/j.proeng.2015.08.708},
  pages     = {540 -- 543},
  year      = {2015},
  abstract  = {An amperometric enzyme biosensor has been applied for the detection of adrenaline. The adrenaline biosensor has been prepared by modification of an oxygen electrode with the enzyme laccase that operates at a broad pH range between pH 3.5 to pH 8. The enzyme molecules were immobilized via cross-linking with glutaraldehyde. The sensitivity of the developed adrenaline biosensor in different pH buffer solutions has been studied.},
  language  = {en}
}
@article{SchusserKrischerMolinetal.2015,
  author    = {Schusser, Sebastian and Krischer, M. and Molin, D. G. M. and Akker, N. M. S. van den and B{\"a}cker, Matthias and Poghossian, Arshak and Sch{\"o}ning, Michael Josef},
  title     = {Sensor System for in-situ and Real-time Monitoring of Polymer (bio) degradation},
  series = {Procedia Engineering},
  volume    = {120},
  journal   = {Procedia Engineering},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {1877-7058},
  doi       = {10.1016/j.proeng.2015.08.815},
  pages     = {948 -- 951},
  year      = {2015},
  abstract  = {A sensor system for investigating (bio)degradationprocesses of polymers is presented. The system utilizes semiconductor field-effect sensors and is capable of monitoring the degradation process in-situ and in real-time. The degradation of the polymer poly(d,l-lactic acid) is exemplarily monitored in solutions with different pH value, pH-buffer solution containing the model enzyme lipase from Rhizomucormiehei and cell-culture medium containing supernatants from stimulated and non-stimulated THP-1-derived macrophages mimicking activation of the immune system.},
  language  = {en}
}
@article{BronderPoghossianSchejaetal.2015,
  author    = {Bronder, Thomas and Poghossian, Arshak and Scheja, S. and Wu, Chunsheng and Keusgen, M. and Sch{\"o}ning, Michael Josef},
  title     = {Electrostatic Detection of Unlabelled Single- and Double-stranded DNA Using Capacitive Field-effect Devices Functionalized with a Positively Charged Polyelectrolyte Layer},
  series = {Procedia Engineering},
  volume    = {120},
  journal   = {Procedia Engineering},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {1877-7058},
  doi       = {10.1016/j.proeng.2015.08.710},
  pages     = {544 -- 547},
  year      = {2015},
  abstract  = {Capacitive field-effect electrolyte-insulator-semiconductor sensors consisting of an Al-p-Si-SiO2 structure have been used for the electrical detection of unlabelled single- and double-stranded DNA (dsDNA) molecules by their intrinsic charge. A simple functionalization protocol based on the layer-by-layer (LbL) technique was used to prepare a weak polyelectrolyte/probe-DNA bilayer, followed by the hybridization with complementary target DNA molecules. Due to the flat orientation of the LbL-adsorbed DNA molecules, a high sensor signal has been achieved. In addition, direct label-free detection of in-solution hybridized dsDNA molecules has been studied.},
  language  = {en}
}
@inproceedings{PoghossianIngebrandtPlatenetal.2006,
  author    = {Poghossian, Arshak and Ingebrandt, S. and Platen, J. and Sch{\"o}ning, Michael Josef},
  title     = {Field-effect sensors with charged macromolecules - from micro towards nano aspects},
  series = {Biochemical Sensing Utilisation of Micro-and Nanotechnologies, Warschau, Nov. 2005 : Lecture Notes of the ICB Seminar / ed.: M. Mascini, W. Torbicz},
  booktitle = {Biochemical Sensing Utilisation of Micro-and Nanotechnologies, Warschau, Nov. 2005 : Lecture Notes of the ICB Seminar / ed.: M. Mascini, W. Torbicz},
  publisher = {Polish Academy Sciences Press},
  address   = {Warsaw},
  pages     = {74 -- 81},
  year      = {2006},
  language  = {en}
}
@article{SchoeningAbouzarIngebrandtetal.2006,
  author    = {Sch{\"o}ning, Michael Josef and Abouzar, Maryam H. and Ingebrandt, Sven and Platen, Johannes and Offenh{\"a}usser, Andreas and Poghossian, Arshak},
  title     = {Towards label-free detection of charged macromolecules using field-effect-based structures : Scaling down from capacitive EIS sensor over ISFET to nano-scale devices},
  series = {Nanostructured materials and hybrid composites for gas sensors and biomedical applications : symposium held April 18-20, 2006, San Francisco , California, U.S.A.},
  journal   = {Nanostructured materials and hybrid composites for gas sensors and biomedical applications : symposium held April 18-20, 2006, San Francisco , California, U.S.A.},
  number    = {paper 0915-R05-04},
  editor    = {Comini, Elisabetta},
  isbn      = {9781558998711},
  pages     = {89 -- 94},
  year      = {2006},
  language  = {en}
}
@article{MolinnusBaeckerIkenetal.2015,
  author    = {Molinnus, Denise and B{\"a}cker, Matthias and Iken, Heiko and Poghossian, Arshak and Keusgen, Michael and Sch{\"o}ning, Michael Josef},
  title     = {Concept for a biomolecular logic chip with an integrated sensor and actuator function},
  series = {Physica status solidi (a)},
  volume    = {212},
  journal   = {Physica status solidi (a)},
  number    = {6},
  publisher = {Wiley},
  address   = {Weinheim},
  issn      = {1862-6319},
  doi       = {10.1002/pssa.201431913},
  pages     = {1382 -- 1388},
  year      = {2015},
  abstract  = {A concept for a new generation of an integrated multi-functional biosensor/actuator system is developed, which is based on biomolecular logic principles. Such a system is expected to be able to detect multiple biochemical input signals simultaneously and in real-time and convert them into electrical output signals with logical operations such as OR, AND, etc. The system can be designed as a closed-loop drug release device triggered by an enzyme logic gate, while the release of the drug induced by the actuator at the required dosage and timing will be controlled by an additional drug sensor. Thus, the system could help to make an accurate and specific diagnosis. The presented concept is exemplarily demonstrated by using an enzyme logic gate based on a glucose/glucose oxidase system, a temperature-responsive hydrogel mimicking the actuator function and an insulin (drug) sensor. In this work, the results of functional testing of individual amperometric glucose and insulin sensors as well as an impedimetric sensor for the detection of the hydrogel swelling/shrinking are presented.},
  language  = {en}
}
@article{BronderPoghossianSchejaetal.2015,
  author    = {Bronder, Thomas and Poghossian, Arshak and Scheja, Sabrina and Wu, Chunsheng and Keusgen, Michael and Mewes, Dieter and Sch{\"o}ning, Michael Josef},
  title     = {DNA Immobilization and Hybridization Detection by the Intrinsic Molecular Charge Using Capacitive Field-Effect Sensors Modified with a Charged Weak Polyelectrolyte Layer},
  series = {Applied Materials \& Interfaces},
  volume    = {36},
  journal   = {Applied Materials \& Interfaces},
  number    = {7},
  publisher = {American Chemical Society},
  address   = {Washington, DC},
  doi       = {10.1021/acsami.5b05146},
  pages     = {20068 -- 20075},
  year      = {2015},
  abstract  = {Miniaturized setup, compatibility with advanced micro- and nanotechnologies, and ability to detect biomolecules by their intrinsic molecular charge favor the semiconductor field-effect platform as one of the most attractive approaches for the development of label-free DNA chips. In this work, a capacitive field-effect EIS (electrolyte-insulator-semiconductor) sensor covered with a layer-by-layer prepared, positively charged weak polyelectrolyte layer of PAH (poly(allylamine hydrochloride)) was used for the label-free electrical detection of DNA (deoxyribonucleic acid) immobilization and hybridization. The negatively charged probe single-stranded DNA (ssDNA) molecules were electrostatically adsorbed onto the positively charged PAH layer, resulting in a preferentially flat orientation of the ssDNA molecules within the Debye length, thus yielding a reduced charge-screening effect and a higher sensor signal. Each sensor-surface modification step (PAH adsorption, probe ssDNA immobilization, hybridization with complementary target DNA (cDNA), reducing an unspecific adsorption by a blocking agent, incubation with noncomplementary DNA (ncDNA) solution) was monitored by means of capacitance-voltage and constant-capacitance measurements. In addition, the surface morphology of the PAH layer was studied by atomic force microscopy and contact-angle measurements. High hybridization signals of 34 and 43 mV were recorded in low-ionic strength solutions of 10 and 1 mM, respectively. In contrast, a small signal of 4 mV was recorded in the case of unspecific adsorption of fully mismatched ncDNA. The density of probe ssDNA and dsDNA molecules as well as the hybridization efficiency was estimated using the experimentally measured DNA immobilization and hybridization signals and a simplified double-layer capacitor model. The results of field-effect experiments were supported by fluorescence measurements, verifying the DNA-immobilization and hybridization event.},
  language  = {en}
}
@article{SchusserKrischerBaeckeretal.2015,
  author    = {Schusser, Sebastian and Krischer, Maximillian and B{\"a}cker, Matthias and Poghossian, Arshak and Wagner, Patrick and Sch{\"o}ning, Michael Josef},
  title     = {Monitoring of the Enzymatically Catalyzed Degradation of Biodegradable Polymers by Means of Capacitive Field-Effect Sensors},
  series = {Analytical Chemistry},
  volume    = {87},
  journal   = {Analytical Chemistry},
  number    = {13},
  publisher = {ACS Publications},
  address   = {Washington, DC},
  issn      = {1520-6882},
  doi       = {10.1021/acs.analchem.5b00617},
  pages     = {6607 -- 6613},
  year      = {2015},
  abstract  = {Designing novel or optimizing existing biodegradable polymers for biomedical applications requires numerous tests on the effect of substances on the degradation process. In the present work, polymer-modified electrolyte-insulator-semiconductor (PMEIS) sensors have been applied for monitoring an enzymatically catalyzed degradation of polymers for the first time. The thin films of biodegradable polymer poly(d,l-lactic acid) and enzyme lipase were used as a model system. During degradation, the sensors were read-out by means of impedance spectroscopy. In order to interpret the data obtained from impedance measurements, an electrical equivalent circuit model was developed. In addition, morphological investigations of the polymer surface have been performed by means of in situ atomic force microscopy. The sensor signal change, which reflects the progress of degradation, indicates an accelerated degradation in the presence of the enzyme compared to hydrolysis in neutral pH buffer media. The degradation rate increases with increasing enzyme concentration. The obtained results demonstrate the potential of PMEIS sensors as a very promising tool for in situ and real-time monitoring of degradation of polymers.},
  language  = {en}
}
@incollection{PoghossianSchusserBaeckeretal.2015,
  author    = {Poghossian, Arshak and Schusser, Sebastian and B{\"a}cker, M. and Leinhos, Marcel and Sch{\"o}ning, Michael Josef},
  title     = {Real-time in-situ electrical monitoring of the degradation of biopolymers using semiconductor field-effect devices},
  series = {Biodegradable biopolymers. Vol. 1},
  booktitle = {Biodegradable biopolymers. Vol. 1},
  publisher = {Nova Science Publ.},
  address   = {Hauppauge},
  isbn      = {978-1-63483-632-6},
  pages     = {135 -- 153},
  year      = {2015},
  language  = {en}
}
@inproceedings{PoghossianBronderWuetal.2015,
  author    = {Poghossian, Arshak and Bronder, Thomas and Wu, Chunsheng and Sch{\"o}ning, Michael Josef},
  title     = {Label-free sensing of biomolecules by their intrinsic molecular charge using field-effect devices},
  series = {Semiconductor Micro- and Nanoelectonics : Proceedings of the tenth international conference, Yerevan, Armenia, September 11-13},
  booktitle = {Semiconductor Micro- and Nanoelectonics : Proceedings of the tenth international conference, Yerevan, Armenia, September 11-13},
  isbn      = {978-5-8084-1991-9},
  pages     = {61 -- 63},
  year      = {2015},
  language  = {en}
}
@article{WuPoghossianBronderetal.2016,
  author    = {Wu, Chunsheng and Poghossian, Arshak and Bronder, Thomas and Sch{\"o}ning, Michael Josef},
  title     = {Sensing of double-stranded DNA molecules by their intrinsic molecular charge using the light-addressable potentiometric sensor},
  series = {Sensors and Actuators B: Chemical},
  journal   = {Sensors and Actuators B: Chemical},
  number    = {229},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0925-4005},
  doi       = {10.1016/j.snb.2016.02.004},
  pages     = {506 -- 512},
  year      = {2016},
  abstract  = {A multi-spot light-addressable potentiometric sensor (LAPS), which belongs to the family of semiconductor field-effect devices, was applied for label-free detection of double-stranded deoxyribonucleic acid (dsDNA) molecules by their intrinsic molecular charge. To reduce the distance between the DNA charge and sensor surface and thus, to enhance the electrostatic coupling between the dsDNA molecules and the LAPS, the negatively charged dsDNA molecules were electrostatically adsorbed onto the gate surface of the LAPS covered with a positively charged weak polyelectrolyte layer of PAH (poly(allylamine hydrochloride)). The surface potential changes in each spot of the LAPS, induced by the layer-by-layer adsorption of a PAH/dsDNA bilayer, were recorded by means of photocurrent-voltage and constant-photocurrent measurements. In addition, the surface morphology of the gate surface before and after consecutive electrostatic adsorption of PAH and dsDNA layers was studied by atomic force microscopy measurements. Moreover, fluorescence microscopy was used to verify the successful adsorption of dsDNA molecules onto the PAH-modified LAPS surface. A high sensor signal of 25 mV was registered after adsorption of 10 nM dsDNA molecules. The lower detection limit is down to 0.1 nM dsDNA. The obtained results demonstrate that the PAH-modified LAPS device provides a convenient and rapid platform for the direct label-free electrical detection of in-solution hybridized dsDNA molecules.},
  language  = {en}
}
@article{BaeckerKochEibenetal.2017,
  author    = {B{\"a}cker, Matthias and Koch, Claudia and Eiben, Sabine and Geiger, Fania and Eber, Fabian and Gliemann, Hartmut and Poghossian, Arshak and Wege, Christina and Sch{\"o}ning, Michael Josef},
  title     = {Tobacco mosaic virus as enzyme nanocarrier for electrochemical biosensors},
  series = {Sensors and Actuators B: Chemical},
  volume    = {238},
  journal   = {Sensors and Actuators B: Chemical},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0925-4005},
  doi       = {10.1016/j.snb.2016.07.096},
  pages     = {716 -- 722},
  year      = {2017},
  abstract  = {The conjunction of (bio-)chemical recognition elements with nanoscale biological building blocks such as virus particles is considered as a very promising strategy for the creation of biohybrids opening novel opportunities for label-free biosensing. This work presents a new approach for the development of biosensors using tobacco mosaic virus (TMV) nanotubes or coat proteins (CPs) as enzyme nanocarriers. Sensor chips combining an array of Pt electrodes loaded with glucose oxidase (GOD)-modified TMV nanotubes or CP aggregates were used for amperometric detection of glucose as a model system for the first time. The presence of TMV nanotubes or CPs on the sensor surface allows binding of a high amount of precisely positioned enzymes without substantial loss of their activity, and may also ensure accessibility of their active centers for analyte molecules. Specific and efficient immobilization of streptavidin-conjugated GOD ([SA]-GOD) complexes on biotinylated TMV nanotubes or CPs was achieved via bioaffinity binding. These layouts were tested in parallel with glucose sensors with adsorptively immobilized [SA]-GOD, as well as [SA]-GOD crosslinked with glutardialdehyde, and came out to exhibit superior sensor performance. The achieved results underline a great potential of an integration of virus/biomolecule hybrids with electronic transducers for future applications in biosensorics and biochips.},
  language  = {en}
}
@article{MolinnusSorichBartzetal.2016,
  author    = {Molinnus, Denise and Sorich, Maren and Bartz, Alexander and Siegert, Petra and Willenberg, Holger S. and Lisdat, Fred and Poghossian, Arshak and Keusgen, Michael and Sch{\"o}ning, Michael Josef},
  title     = {Towards an adrenaline biosensor based on substrate recycling amplification in combination with an enzyme logic gate},
  series = {Sensors and Actuators B: Chemical},
  volume    = {237},
  journal   = {Sensors and Actuators B: Chemical},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0925-4005},
  doi       = {10.1016/j.snb.2016.06.064},
  pages     = {190 -- 195},
  year      = {2016},
  abstract  = {An amperometric biosensor using a substrate recycling principle was realized for the detection of low adrenaline concentrations (1 nM) by measurements in phosphate buffer and Ringer's solution at pH 6.5 and pH 7.4, respectively. In proof-of-concept experiments, a Boolean logic-gate principle has been applied to develop a digital adrenaline biosensor based on an enzyme AND logic gate. The obtained results demonstrate that the developed digital biosensor is capable for a rapid qualitative determination of the presence/absence of adrenaline in a YES/NO statement. Such digital biosensor could be used in clinical diagnostics for the control of a correct insertion of a catheter in the adrenal veins during adrenal venous-sampling procedure.},
  language  = {en}
}