The PERN eLibrary is an important and unique reference tool for classic population-environment literature; journal articles; conference and working papers; relevant data sets; and educational resources. The eLibrary database is annotated and includes bibliographic citation information, Internet links to the materials, and keywords.
The Environmental Treaties and Resource Indicators (ENTRI) Query Service is a comprehensive Web-based application for accessing environmental treaty texts and treaty status data such as signatories, parties, former parties (if applicable), year of agreement and enforcement and other related information. Through the treaty locator and country explorer search capabilities, treaties that focus on land use/and cover change, desertification, global climate change, stratospheric ozone depletion, transboundary air pollution, conservation of biological diversity, deforestation, ocean and their living resources, trade and the environment, and population can be retrieved. In addition, selected remote sites can be queried to retrieve large document collections related to environmental treaties. ENTRI Query Service is produced by Columbia University Center for International Earth Science Information Network (CIESIN), in collaboration with the International Union for the Conservation of Nature (IUCN), United Nations Environmental Programme (UNEP), Tufts University's Fletcher School of Law and Diplomacy (FSLD), British Columbia Ministry of Environment, Lands, & Parks (BCMELP), Antarctic Cooperative Research Centre (ACRC) and American Society of International Law (ASIL).