Robert Williams signed books all day long for an endless line of fans on March 28 at the Los Angeles Municipal Art Gallery. His new book, SLANG Aesthetics!, serves as an exhibition guide to the comprehensive retrospective by the same name. The exhibit opened last February at the same venue where the signing took place. It’s on view through April 19 in tandem with Juxtapoz Magazine’s anniversary group show, “20 Years Under the Influence of Juxtapoz.” SLANG Aesthetics! covers Williams’ expansive career as an artist, a founder of Juxtapoz, and arguably the godfather of low brow art and culture.