“Etudes de Bluets et de Paquerelles.” Image 5. Collection of the BnF Gallica, the National Library of France. In the public domain due to age. via https://gallica.bnf.fr/ark:/12148/btv1b52512760g/f5.item“Études de capucines, et Lierre.” Image 13. Collection of the BnF Gallica, the National Library of France. In the public domain due to age. via b