OAuth
Implementing OAuth 2.0 with Node.js - Soham Kamani
Understanding and Implementing OAuth2 in Node.js - Diogo Souza
Implementing an OAuth Server with Node.js and Express - Valeri Karpov
Express JS OAuth 2 server using oauth2-server package - Nick B. Alcala
Passport
Node.js and Express authentication using Passport - Dan Arias