1. Medida de la erosion hidrica de un Entisol de la Selva Alta (San Ramon - Chanchamayo) bajo diferentes sistemas de cultivo;Alegre,1979
2. A provisional methodology for soil degradation assessment;Anonymous,1979
3. A compilation of federal state stream standards on (i) general stream use designations, (ii) temperature, (iii) turbidity, (iv) bacteria;Anonymous,1972
4. A provisional methodology for soil degradation assessment;Anonymous,1979
5. Clasification de las tierras del Perú;Anonymous,1982