J.H. ENGSTROM, a Swedish photographer, moved to Paris when he was 19. For more than 20 years he has documented the city's underside—the dingy trains, back alleys, sloppy kisses and hard-edged hustlers—revealing a Paris that is far more vital than its reputation. Aperture has recently published 250 of these colour and black-and-white photographs in a book called "Sketch of Paris". We have selected a few of these images for a slideshow here.