CARDONA, Tomas D.; PRESBITERO, Alan L. NOTE: PROCTOR DENSITY OF UMINGAN CLAY LOAM, MAASIN CLAY AND MALITBOG CLAY. Annals of Tropical Research, [S. l.], v. 10, n. 1, p. 47–51, 1988. Disponível em: https://atr.vsu.edu.ph/article/view/639. Acesso em: 5 dec. 2025.