Hipgnosis, the Album Artists Who Made Pink Floyd's Pig Fly - The New York Times

Animals', Pink Floyd's most aggressive album, turns 47

Hipgnosis: the rock stars of album cover design

Hipgnosis' Album Covers From Pink Floyd to Led Zeppelin

Pink Floyd's “Animals”: The Story Behind the Album Cover, by David Deal

Pink Floyd The Official Site

Hear preview of new Pink Floyd album, The Endless River. - The San Diego Union-Tribune

The Art of Hipgnosis

Omnireviewer (Pink Floyd stamps edition)

The Ibiza Cut: Interviews with Hipgnosis from 2010 – No More Big Wheels

Dec 3, 1976: Pink Floyd Flying Pig Gets Loose