APA (7th ed.) Citation

Tang, W., & Selwood, J. (2005). Spatial portals: Gateways to geographic information. ESRI Press.

Chicago Style (17th ed.) Citation

Tang, Winnie, and Jan Selwood. Spatial Portals: Gateways to Geographic Information. Redlands, Calif.: ESRI Press, 2005.

MLA (9th ed.) Citation

Tang, Winnie, and Jan Selwood. Spatial Portals: Gateways to Geographic Information. ESRI Press, 2005.

Warning: These citations may not always be 100% accurate.