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| Insects, The Hidden Treasures of Mahausakande | Jayanthi | Edirisinghe | 2019 | General |
| Insecurity of Tamils in Sri Lanka | Tamil Information Centre | N/A | 1983 | General |
| Inside An Elusive Mind - Prabhakaran | M. R. | Narayan Swamy | 2003 | General |
| Inside Story, The - Some Aspects of My Parliamentary Experience | Hugh | Fernando | 1965 | Politics |
| Insights Into The Sri Lanka Economy 1970-1980 - Logos, Vol 19, No 4, 1980 | Centre For Society & Religion | N/A | 1980 | General |
| Inspirational Gardens of Sri Lankans in Victoria, Australia | Alexander Asoka | Dassanaike | 2011 | General |
| Instability of an Export Economy, The | Gamani | Corea | 1975 | General |
| Institute of Engineers, The - Transactions for 1975 | Institute of Engineers | N/A | 1976 | General |
| Institutes of the Laws of Ceylon - Vol 1 | Henry Byerley | Thomson | 1866 | General |
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