1] prof Emil Hnatko ENVIRONMENTAL ASSESSMENT OF BIO RESOURCES AND RENEWABLE/RECURRENT ENERGY SOURCES IN AGRICULTURE" - 12. Međunarodna konferencija o dostignućima elektrotehnike, mašinstva i informatike, 11.05.2015.
(https://ekonferencije.com/en/paper/environmental-assessment-of-bi/3548)

2] prof Emil Hnatko AN ENVIRONMENTAL IMPACT ASSESSMENT RAW MATERIALS AND RENEWABLE/RENOVATE SOURCE ENERGY IN FARM MACHINERY" - 12. Međunarodna konferencija o dostignućima elektrotehnike, mašinstva i informatike, 17.03.2015.
(https://ekonferencije.com/en/paper/an-environmental-impact-assess/3214)