TY - BK ED - World Congress of Soil Science, 15 TI - Commission IV: Poster sessions SN - 968-6201-25-4 U1 - 631.4 PY - 1994/// CY - Acapulco, Gro. (Mexico) PB - International Society of Soil Science|Mexican Society of Soil Science|INEGI, N1 - v. 5b ER -