Burgert-Brucker, Clara R., Trinadh Dontamsetti, Aileen Mashall, and Pete Gething. 2016. Guidance for use of The DHS Program modeled map surfaces. DHS Spatial Analysis Reports No. 14. Rockville, Maryland, USA: ICF International. Available at http://dhsprogram.com/pubs/pdf/SAR14/SAR14.pdf.