Illustrator and anarchist Clifford Harper, whose family had an occupational history in the postal service, designed stamps "for post-revolutionary post" bearing the image of anarchist figures such as Pierre-Joseph Proudhon ("property is theft"), Oscar Wilde, Emma Goldman and Emiliano Zapata. Colin Ward, along with Harper, published a book in 1997 called "Stamps: Designs For Anarchist Postage Stamps", containing an essay by Ward on the subject of anarchists and postage stamps. Fund-raising stamps with anti-state messages have appeared within labor unions such as the ones printed by the Confederación Nacional del Trabajo, and the Industrial Workers of the World.