Biodiversity Heritage Library

The Biodiversity Heritage Library (BHL) is the world’s largest open-access digital library for biodiversity literature and archives. BHL operates as a worldwide consortium of natural history, botanical, research, and national libraries working together to address this challenge by digitizing the natural history literature held in their collections and making it freely available for open access as part of a global "biodiversity community".

Source: Wikipedia — Biodiversity Heritage Library (CC BY-SA 4.0)