Page 20 of Illustriertes Prachtwerk sämtlicher Tauben-rassen. 1906. Lithograph based on a watercolor template by Anton Schöner. In the public domain due to age. Collections of the American Museum of Natural History Library. In the public domain due to age. via https://www.biodiversitylibrary.org/item/106229#page/20/mode/2upPage 22 of Illustriertes Prachtwerk sämtlicher Tauben-rassen. 1906. Lithograph based on a watercolor template by Anton Schöner. In the public domain due to age. Collections of the American Museum of Natural History Library. In the public domain due to age. via https://www.biodiversitylibrary.org/item/106229#page/20/mode/2upPage 24 of Illustriertes Prachtwerk sämtlicher Tauben-rassen. 1906. Lithograph based on a watercolor template by Anton Schöner. In the public domain due to age. Collections of the American Museum of Natural History Library. In the public domain due to age. via https://www.biodiversitylibrary.org/item/106229#page/20/mode/2up
Ramphastos culmenatus. Culmenated toucan. Image 2 from A monograph of the Ramphastidae, or family of toucans. 1833. Edward Lear, maker. Collections of the Smithsonian Libraries. Biodiversity Heritage Library, digitalizing sponsors. In the public domain due to age. via https://archive.org/details/monographrampha00goul/page/2/mode/1upRamphastos Cuvieri (Wagler) Cuvier’s Toucan. Image 3 from A monograph of the Ramphastidae, or family of toucans. 1833. Drawn from nature and on stone by John and Elizabeth Gould. Collections of the Smithsonian Libraries. Biodiversity Heritage Library, digitalizing sponsors. In the public domain due to age. via https://archive.org/details/monographrampha00goul/page/3/mode/1upRamphastos erythrorhynchus(auct). Red billed toucan. Image 4 from A monograph of the Ramphastidae, or family of toucans. 1833. Drawn by Edward Lear. Collections of the Smithsonian Libraries. Biodiversity Heritage Library, digitalizing sponsors. In the public domain due to age. via https://archive.org/details/monographrampha00goul/page/4/mode/1up