Google's mission is to organize the world's information and make it universally accessible and useful.

Online collaborative writing, citing, hosting of data and publishing.

Annotate the web, with anyone, anywhere.

Perma.cc is simple, easy to use, and is built and supported by libraries.

Papers helps you collect and curate your research material.

An open citations index for scientific publications.

An easy and intuitive way to discover, read, annotate, write and share scientific research.

Scientific platform to research and curate the entire corpus of phenomenology.

Read, annotate, and share PDFs and more.

Public search engine and digital library for scientific and academic papers.