European Community, Astorga, Y., Castillo, L., Coto Campos, J. M., Pauw, N., & Persoone, G. (1997). Development and application of cost-effective methods for biological monitoring of rivers in Costa Rica: Final report 1997. [Heredia]: [Universidad Nacional, C.R.].

European Community, Y. Astorga, L. Castillo, Juana María Coto Campos, N.De Pauw, and G. Persoone. Development and Application of Cost-effective Methods for Biological Monitoring of Rivers in Costa Rica: Final Report 1997. [Heredia]: [Universidad Nacional, C.R.], 1997.

European Community, et al. Development and Application of Cost-effective Methods for Biological Monitoring of Rivers in Costa Rica: Final Report 1997. [Heredia]: [Universidad Nacional, C.R.], 1997.