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| Preface | |
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| Introduction | |
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| Sensor | |
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| Recorder | |
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| Stations and networks | |
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| Arrays | |
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| Instrument correction and calibration | |
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| Seismic sensors | |
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| The standard inertia seismometer | |
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| Seismometer frequency response | |
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| Seismometer frequency response, alternative solution | |
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| The velocity transducer | |
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| Electromagnetic damping | |
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| Polarity convention | |
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| Instrument response curves, different representation | |
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| Sensor response to transient signals | |
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| Damping constant | |
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| Construction of seismic sensors | |
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| The Wood Anderson short period torsion sensor | |
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| Long period sensors | |
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| Garden-gate | |
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| Inverted pendulum | |
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| LaCoste | |
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| Sensor calibration coil | |
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| Active sensors | |
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| Accelerometers | |
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| Velocity broadband sensors | |
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| Extending the frequency response, inverse filtering and feed back | |
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| Theoretical aspects of active sensors | |
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| General response of a feedback system | |
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| The basic Force-Balanced Accelerometer | |
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| Broadband feedback seisometers | |
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| Other feedback techniques | |
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| Sensor self noise | |
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| Noise in passive sensors coupled to amplifiers, theoretical aspects | |
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| Some new trends in seismic sensors | |
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| Seismometers with electrochemical transducers | |
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| Micromachined accelerometers and seismometers | |
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| Sensor parameters | |
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| Frequency response | |
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| Sensitivity | |
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| Sensor dynamic range | |
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| Sensor linearity | |
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| Sensor cross axis sensitivity | |
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| Sensor gain and output | |
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| Examples of sensors | |
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| Exploration type 4.5 Hz geophone | |
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| Short period sensor, the L4-C | |
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| Accelerometer, the Kinemetrics Episensor | |
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| Broadband sensors, the Streckeisen STS-1 and STS-2 and Guralp CMG-3T | |
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| Negative feedback sensors, Lennartz LE-3D | |
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| Borehole sensors | |
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| Summary of sensor specifications | |
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| Which sensor to choose | |
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| Seismic noise | |
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| Observation of noise | |
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| Noise spectra | |
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| Relating power spectra to amplitude measurements | |
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| Origin of seismic noise | |
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| Analog to digital converter | |
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| Example of a simple analog to digital converter, the Flash ADC | |
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| Basic ADC properties | |
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| A typical ADC, the Ramp ADC | |
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| Multi channel ADC | |
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| Digitizers for a higher dynamic range | |
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| Oversampling for improvement of the dynamic range | |
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| Sigma Delta ADC, SDADC | |
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| How sigma-delta improves digitization noise: theory | |
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| Aliasing | |
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| Anti alias filters | |
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| Examples of digitizers | |
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| Seismic Recorders | |
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| Analog amplifier | |
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| Differential input-output | |
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| Analog filters | |
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| Amplifier specifications and noise | |
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| Analog recording | |
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| Introduction to digital recorders | |
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| Digitizing | |
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| Time stamping of data | |
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| Storage media and recording in a ring buffer | |
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| Seismic triggers | |
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| Summary of trigger parameters and their settings | |
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| Communication and data retrieval | |
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| Public domain data acquisition systems | |
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| Seismic recorders in use | |
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| The next generation recorder | |
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| Examples of recorders | |
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| Which recorder to choose | |
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| Correction for instrument response | |
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| Linear systems | |
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| Spectral analysis and the Fourier transform | |
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| Noise power spectrum | |
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| General instrument correction in frequency and time domain | |
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| General representation of the frequency response function | |
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| Anti alias filters | |
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| Instrument correction and polarity | |
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| Combining response curves | |
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| Common ways of giving response information | |
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| GSE | |
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| SEED | |
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| SEISAN | |
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| Seismic stations | |
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| Geographical location of a seismic station | |
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| Site selection and seismic noise survey | |
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| Installation of the seismic station | |
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| Sensor installation | |
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| Broadband sensor installation | |
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| Borehole installations | |
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| What is a good VLP station | |
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| Temporary installation of seismic stations | |
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| Lightning and over-voltage protection | |
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| Power | |
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| Stations running off the main AC supply | |
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| Batteries | |
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| Power sources | |
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| Solar cells | |
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| Wind generators | |
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| Fuel cells | |
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| Seismic networks | |
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| Purpose of seismic networks | |
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| Network geometry | |
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| Network configuration: physical and virtual networks | |
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| Physical seismic networks | |
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| Communication standards | |
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| Virtual seismic networks | |
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| The choice between physical and virtual seismic systems | |
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| Seismic data transmission | |
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| Analog data transmission | |
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| Radio links | |
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| Simplex-duplex | |
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| Point to point or point to multi point radio networks | |
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| Spread spectrum | |
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| Radio link construction and equipment | |
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| Radio links with repeater stations | |
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| Telephone and satellite | |
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| Digital data transmission protocols and some examples of their use | |
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| Serial data communication | |
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| TCP/IP communication | |
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| Compression of digital data | |
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| Error correction methods used with seismic signals | |
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| Seismic data transmission and timing | |
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| Communication and graphics | |
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| Examples of networks | |
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| Running a seismic network | |
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| Physical operation | |
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| Data processing | |
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| How to make your own network | |
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| Seismic arrays | |
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| Basic array parameters | |
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| Array transfer function | |
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| Instruments characteristics | |
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| Field arrangement | |
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| Example of a portable array | |
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| Calibration and testing | |
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| Test equipment and recording of test signals | |
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| Sensors | |
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| Sensor free period | |
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| Seismometer damping | |
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| Determining calibration coil motor constant | |
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| Polarity and sensor orientation | |
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| Frequency response using harmonic drive methods | |
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| Lissajous figures | |
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| Methods for absolute calibration of a sensor | |
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| Shaking table | |
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| Using the ground as a shaking table | |
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| Calibration by stepwise motion | |
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| Determining sensitivity of accelerometer by tilt | |
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| Use of the calibration pulse | |
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| Using pseudo random signals for calibration | |
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| Recorder | |
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| Measuring instrument self noise | |
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| Example of a practical noise measurement | |
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| Basic electronics | |
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| Basic terms | |
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| Electric charge | |
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| Electric potential, current and power | |
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| Kirchhoff laws | |
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| Passive components | |
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| Resistors, inductors and capacitors | |
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| Connection of components in series and parallel | |
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| A passive non-linear component: the diode | |
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| DC and AC signals | |
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| Decibels | |
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| Complex impedances and response | |
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| Power supply | |
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| Common laboratory instruments | |
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| Amplifiers | |
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| Basic amplifier configurations | |
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| Active filters | |
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| Introduction to logical circuits | |
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| Example: A daily calibration sequence generator for seismometers | |
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| References | |
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| Company references | |
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| Index | |