Vere Foster's simple lessons in water-color, flowers : eight facsimiles of original water-color drawings and numerous outline drawings of flowers, after various artists, with full instructions for drawing and painting (1884)
Foster, Vere, 1819-1900 · London : Blackie & Son · leaf 33
THE AZALEA. These beautiful plants are nearly allied to the Rhododendrons, and are natives of North America, Turkey, and China; but the great care and skill that has been bestowed on their cultivation since they were brought to Europe has developed their flowers to an extent superior in many cases…
Watercolor painting
Internet Archive · Getty Research Institute · Public domain (published before 1931). Free to use for anything.