1. Global Rural-Urban Mapping Project, Version 1 (GRUMPv1): Population Density Grid;Ciesin,2011
2. The 2018 Revision (ST/ESA/SER.A/420),2019
3. Soil invertebrates and ecosystem services;Lavelle;Eur. J. Soil Biol.,2006
4. The diversity of soil communities, the “poor man's tropical rainforest,”;Giller;Biodivers. Conserv.,1996
5. Urban SOIL MANAGEMENT: a GROWING concern;De Kimpe;Soil Sci.,2000