Cottrell, D. (2013). The Magic Question. TMH.
Chicago Style aipamenaCottrell, David. The Magic Question. New delhi: TMH, 2013.
MLA aipamenaCottrell, David. The Magic Question. TMH, 2013.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.
Cottrell, D. (2013). The Magic Question. TMH.
Chicago Style aipamenaCottrell, David. The Magic Question. New delhi: TMH, 2013.
MLA aipamenaCottrell, David. The Magic Question. TMH, 2013.