APA:
Nikolov, Boris P., Stoyanov, George, Ragyov, Dimitar, Shurulinkov, Peter, Nikolov, Ivailo Petrov (2008). High-altitude records of the great grey shrike Lanius excubitor in Bulgaria during migration and winter.
Acrocephalus, letnik 29, številka 138/139, str. 185-186.
URN:NBN:SI:DOC-UTUT9XYU from http://www.dlib.si
MLA:
Nikolov, Boris P., Stoyanov, George, Ragyov, Dimitar, Shurulinkov, Peter, Nikolov, Ivailo Petrov. "High-altitude records of the great grey shrike Lanius excubitor in Bulgaria during migration and winter."
Acrocephalus letnik 29. številka 138/139 (2008) str. 185-186.
<http://www.dlib.si/?URN=URN:NBN:SI:DOC-UTUT9XYU>