Freckman DW, Reichman O. Experimental Approaches to Investigate Belowground Animal Diversity. In: Sala OE, Jackson R, Mooney H, Howarth R Methods in Ecosystem Science. Methods in Ecosystem Science. New York: Springer Verlag; 2000:318-329.

Sala OE, Kinzig A, Leemans R, et al. Global biodiversity scenarios for the year 2100. Science. 2000;287:1770-1774. doi:LTER.