Korpijärvi , Juha. 2009. "Economical Model for Maintenance of Electric Distribution System". Записки Горного института 181 (март), 105-8. https://pmi.spmi.ru/pmi/article/view/7041.

Korpijärvi , Juha. 2009. "Economical Model for Maintenance of Electric Distribution System". Journal of Mining Institute 181 (March), 105-8. https://pmi.spmi.ru/pmi/article/view/7041.