Chmielewski, T., D. Golański, M. Węglowski, K. Kudła, and K. Wojnarowski. “The Application of MAG-Speedroot Method for Welding of Root Pass in Butt Welded Pipe Joints”. Welding Technology Review, vol. 85, no. 10, Oct. 2013, doi:10.26628/wtr.v85i10.187.