The painter Edward Edwards said in his Anecdotes of Painters (1808): "Mr. Gainsborough's manner of penciling was so peculiar to himself, that his work needed no signature".https://museumsandcollections.unimelb.edu.au/__data/assets/pdf_file/0003/2942274/13_Ritchie_Gainsboroughs-signature-22.pdf Examples of strongly individual styles include: the Cubist art of Pablo Picasso, the Pop Art style of Andy Warhol, Impressionist style of Vincent Van Gogh, Drip Painting by Jackson Pollock
