The estimation of size and position of contaminating particle adhering to the insulating spacer surface in gas-insulated systemsYasin Khan, Firmansiah Nur Budiman, Abderrahmane Béroual, Nazar Hussain Malik and Abdulrehman Ali Al-ArainyEur. Phys. J. Appl. Phys., 62 2 (2013) 20801DOI: https://doi.org/10.1051/epjap/2013130007