Articles

Coring Magazine, August 2023

"The importance of instrument calibration: Scale factor error – Part 2"

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Coring Magazine, May 2023

"The importance of instrument calibration - Part 1"

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Coring Magazine, January 2022

“A technical note on dogleg severity”

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Coring Magazine, March 2021

"Technical interview with Dag Billger and Duncan McLeod"

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Africa Outlook Magazine, Nr 90 2020

"Trevali company profile"

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Bergsmannen, Nr 3 2020

"TwinGyro mäter rätt i komplicerade borrhål"

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Borrsvängen, Nr 3 2020

"Mikrogyro sparar tid och ger mer data"

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Coring Magazine, April 2020

"Comparing multishot & continuous surveys using the TwinGyro"

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Coring Magazine, February 2019

"Similarities between magnetic and north-finding survey tools"

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3rd International Symposium on Block and Sublevel Caving 

"Methodology for up-hole drilling accuracy
measurements at Kiruna SLC mine"


Wimmer, Nordqvist & Billger. 3rd International Symposium on Block and Sublevel Caving (pp. 625-637). Santiago, Chile: Universidad de Chile. Jan 1, 2014