Virgin and Child with the Young Saint John the Baptist by Antonio da Correggio https://www.rawpixel.com/image/8961586/virgin-and-child-with-the-young-saint-john-the-baptist-antonio-correggioFree Image from public domain licensePNG Poppy outline sketch drawing flower petal. https://www.rawpixel.com/image/14330447/png-poppy-outline-sketch-drawing-flower-petalView licenseOutline View of the Half Dome - 4967 ft., Yo Semite by Carleton Watkins https://www.rawpixel.com/image/14275920/outline-view-the-half-dome-4967-ft-semite-carleton-watkinsFree Image from public domain license