APA
DEWAARDM P. W. F., . (1969). Foliar diagnosis nutrition and yield stability of black pepper(piper nigram L)in Sarawak. Amsterdam: Dept of Agr Res.
Chicago
DEWAARDM P W F, . 1969. Foliar diagnosis nutrition and yield stability of black pepper(piper nigram L)in Sarawak. Amsterdam: Dept of Agr Res.
Harvard
DEWAARDM P. W. F., . (1969). Foliar diagnosis nutrition and yield stability of black pepper(piper nigram L)in Sarawak. Amsterdam: Dept of Agr Res.
MLA
DEWAARDM P W F, . Foliar diagnosis nutrition and yield stability of black pepper(piper nigram L)in Sarawak. Amsterdam: Dept of Agr Res. 1969.