Gamez, Carlos: 'Lifecycle management of power transformers in a new energy era' (Energy Engineering, 2018), 'Power Transformer Condition Monitoring and Diagnosis', Chap. 7, pp. 239-258, DOI: 10.1049/PBPO104E_ch7
IET Digital Library, https://digital-library.theiet.org/;jsessionid=3hkhim170jthx.x-iet-live-01content/books/10.1049/pbpo104e_ch7