Relief printing - Wikipedia
Your Guide to the Printmaking Process
etching
Printmaking Meets Laser Engraving - Ignite Studio at HEPL
Relief Printing with the Fome Etching Press - Jackson's Art Blog
Introduction to Printmaking! - The Deckle Edge
Blake's Relief-Etching Method, John W. Wright, Blake/An Illustrated Quarterly
Choosing the Best Linocut Carving Tools for Block Printing — Linocut Artist
Printmaking Materials: Relief, Etching & More