1. Assoc. Prof., PhD Svilen Rachev (2015) "STUDY OF THE ENERGY POTENTIAL OF RENEWABLE ENERGY SOURCES IN THE REGION OF GABROVO FOR USE IN HYBRID WIND-PHOTOVOLTAIC STAND-ALONE SYSTEM" - Contemporary Materials 2015 - Savremeni Materijali
(https://ekonferencije.com/hr/rad/study-of-the-energy-potential-/4053)

2. Assoc. Prof., PhD Svilen Rachev (2015) "ANALYSYS OF THE PERFORMANCE OF SMALL WIND TURBINES DARIUS AND OPTIONS FOR THEIR INTEGRATION IN BUILDINGS" - Contemporary Materials 2015 - Savremeni Materijali
(https://ekonferencije.com/hr/rad/analysys-of-the-performance-of/4051)

3. Assoc. Prof., PhD Svilen Rachev (2013) "ELECTRIC DRIVE OF TWO-AXES TRACKING SYSTEM FOR PHOTO-VOLTAIC MODULES" - Contemporary Materials - 2013 - Savremeni materijali
(https://ekonferencije.com/hr/rad/electric-drive-of-two-axes-tra/2315)