Gaya APA
Walker, M. et al (2008).
The relative importance of resources and natural enemies in determining herbivore abundance: thistles, tephritids and parasitoids .
London:
British Ecological Society.
Gaya MLA
Walker, Matthew. et al.
"The relative importance of resources and natural enemies in determining herbivore abundance: thistles, tephritids and parasitoids".
London:
British Ecological Society,
2008.
e-journal.