Stoyanov, I.,
Yanev, S., &
Petkov, P.
().
Optimising the operation of a photovoltaic system using cogeneration. // <I>Proc.<D> Union of scientists - Ruse. Fifth intern. conf. "Energy efficiency and agricultural engineering", EE&AE, Ruse, Bulgaria, 17-18 may 2013, 2013, p. 242-247..