Gaya APA
chairman, M, J, T, A. et al (1974).
Standard methods : for the examination of water and wastewater (3).
Amerika:
American Public health Association.
Gaya MLA
chairman, Michael, J., Taras,, AWWA,. et al.
"Standard methods : for the examination of water and wastewater".
3
Amerika:
American Public health Association,
1974.
Text.