1955 to 2000", Soil and Tillage Research, 61 (1–2): 3–12 [3]. Lee, Sunggyu (2006), Encyclopedia of Chemical Processing, CRC Press, . Livingston, Morna & Beach, Milo (2002), Steps to Water: The Ancient Stepwells of India, Princeton Architectural Press, . Lock, Stephen etc. (2001), The Oxford Illustrated Companion to Medicine, Oxford University Press, . Lowe, Robson (1951), The Encyclopedia of British Empire Postage Stamps, 1661–1951 (vol. 3). MSNBC (2008), "Dig uncovers ancient roots of dentistry". Nair, C.G.R. (2004), "Science and technology in free India", Government of Kerala—Kerala Call, Retrieved on 2006-07-09. O'Connor, J. J. & Robertson, E.F. (1996), "Trigonometric functions", MacTutor History of Mathematics Archive. O'Connor, J. J. & Robertson, E. F. (2000), "Paramesvara", MacTutor History of Mathematics archive. Partington, James Riddick & Hall, Bert S. (1999), A History of Greek Fire and Gunpowder, Johns Hopkins University Press, . Peabody, Norman (2003), Hindu Kingship and Polity in Precolonial India, Cambridge University Press, . Peele, Stanton & Marcus Grant (1999), Alcohol and Pleasure: A Health Perspective, Psychology Press, . Piercey, W. Douglas & Scarborough, Harold (2008), hospital, Encyclopædia Britannica. Pingree, David (2003), "The logic of non-Western science: mathematical discoveries in medieval India", Daedalus, 132 (4): 45–54. Raja, Rajendran (2006), "Scientists of Indian origin and their contributions", Encyclopedia of India (Vol 4.) edited by Stanley Wolpert, . Rao, S. R. (1985), Lothal, Archaeological Survey of India. Rodda & Ubertini (2004), The Basis of Civilization—Water Science?, International Association of Hydrological Science, . Roy, Ranjan (1990), "Discovery of the Series Formula for by Leibniz, Gregory, and Nilakantha", Mathematics Magazine, Mathematical Association of America, 63 (5): 291–306. Sanchez & Canton (2006), Microcontroller Programming: The Microchip PIC, CRC Press, . Savage-Smith, Emilie (1985), Islamicate Celestial Globes: Their History, Construction, and Use, Smithsonian Institution Press, Washington, D.C. Schwartzberg, Joseph E. (2008), "Maps and Mapmaking in India", Encyclopaedia of the History of Science, Technology, and Medicine in Non-Western Cultures (2nd edition) edited by Helaine Selin, pp. 1301–1303, Springer, . Seaman, Lewis Charles Bernard (1973), Victorian England: Aspects of English and Imperial History 1837–1901, Routledge, . Seidenberg, A. (1978), The origin of mathematics, Archive for the history of Exact Sciences, 18: 301–342. Sellwood, D. G. J. (2008), coin, Encyclopædia Britannica. Shaffer, Lynda N., "Southernization", Agricultural and Pastoral Societies in Ancient and Classical History edited by Michael Adas, pp. 308–324, Temple University Press, . Sharpe, Peter (1998), Sugar Cane: Past and Present, Southern Illinois University. Siddiqui, I. H. (1986), "Water Works