Texas A and M University, U.S.A.: M.Sc. Degree in Rangeland Ecology and Management (1995-1997).
Soil, Erosion and Conservation as Affected by Land use and Land Tenure, El Pital Watershed, Nicaragua: Technical Bulletin Number 99-3. Soil Management CRSP, Texas A and M University, USA, 1999, Somarriba, M.T. Thurow and A. Thurow.
Diagnostic of Research in Sustainable Agriculture in Hillsides (ASEL) in Nicaragua Developed by UNA for 1990- 1998 (National Agrarian University, Managua, Nicaragua), 2000, Mu.oz, R. and M. Somarriba.
Evaluation of the Possible Climatic Change over Potential Yield on Corn Crop (Zea Mays L.) in the Pacific Region from Nicaragua: Thesis for B.Sc. in Agronomy, National Agrarian University, Managua, Nicaragua,2000, Palma, S. and M. Somarriba.