AGRICOLA serves as the catalog and index of the U.S. National Agricultural Library. All aspects of agriculture and allied disciplines are covered. It is primarily a citation-only database with some full-text material.
AGRIS is a global database providing access to bibliographic information on agricultural science and technology, including grey literature not available through normal publication and distribution channels.
American FactFinder is an online source of U.S. Census information created by the United States Census Bureau. Data provided include population, housing, economic, and geographic information from the United States, Puerto Rico, and the Island Areas.
The Anthropological Index Online is a database of articles based on the journal holdings of the Anthropology Library at the British Museum. The index covers the subjects of socio-cultural and physical anthropology, archaeology, linguistics, and cultural ethnography, providing a broad geographical range of information in each topic.
The Aquatic Plant Information Retrieval System (APIRS) database contains citation and keyword records for scientific articles and reports about uncounted species of aquatic, wetland and invasive plants.
The Association of Religion Data Archives (ARDA) hosts a collection of material includes data on churches and church membership, religious professionals, and religious groups (individuals, congregations, and denominations).
The ADS is a NASA-funded project that contains bibliographic records in astronomy and physics from both peer-reviewed and non-peer-reviewed sources. ADS consists of four databases: Astronomy and Astrophysics, Instrumentation, Physics and Geophysics, and preprints in Astronomy.