Buttenfield, Barbara P., Vanessa Bauman, and R.J. Kern. “Spying With Maps: Surveillance Technologies and the Future of Privacy”. Cartographic Perspectives, no. 44 (March 1, 2003): 70–72. Accessed February 15, 2025. https://cartographicperspectives.org/index.php/journal/article/view/cp44-buttenfield-et-al.