References
- Hamazaki , T. and Paningbatan , E.P. Jr. 1988 . Procedures for soil analysis , Los Baños : Department of Soil Science, University of the Philippines .
- Tokudome . 1994 . Soil profile description and some laboratory data of the soils in the soil tanks at San Ildefonso Bulacan , Edited by: Tem , JICA Expert . 99 – 110 . 1989 – 1994 . Technical Report on the Soil Research Development Center Project .