APA
(1980). Standard methods of analysis for soil, plant tissue, water & fertilizer. Los Banos, Laguna: Philippine Council for Agriculture & Resources Research.
Chicago
1980. Standard methods of analysis for soil, plant tissue, water & fertilizer. Los Banos, Laguna: Philippine Council for Agriculture & Resources Research.
Harvard
(1980). Standard methods of analysis for soil, plant tissue, water & fertilizer. Los Banos, Laguna: Philippine Council for Agriculture & Resources Research.
MLA
Standard methods of analysis for soil, plant tissue, water & fertilizer. Los Banos, Laguna: Philippine Council for Agriculture & Resources Research. 1980.