Gaya APA
Simeonova, V., Nenov, N. (2010).
International Chemistry Olympiads - Problems & Solutions .
Lexington, USA:
s.n..
Gaya MLA
Simeonova, V.., Nenov, N..
"International Chemistry Olympiads - Problems & Solutions".
Lexington, USA:
s.n.,
2010.
Text.