Gaya APA
Puhalla, J., Mike, I, K, J, I, G. (1999).
Sports fields: manual for design, construction and maintenance .
New Jersey:
.
Gaya MLA
Puhalla, Jim., Mike, I., Krans,, Jeff, II., Gotaley,.
"Sports fields: manual for design, construction and maintenance".
New Jersey:
,
1999.
.