“Aranjuez Garden, Arbor, II.” 1907. Collection of the Museo Nacional Centro de Arte Reina Sofía, Madrid. Cc0 license 1.0. via Museo Nacional Centro de Arte Reina Sofía
“Sunset, Tropical Marshes, Florida.” ca. 1880. Oil on canvas. Martin Johnson Heade, artist (1819-1904). Collection of the Morse Museum. In the public domain in the United States because the artist has been dead over 70 years. via http://www.morsemuseum.org/collection-highlights/paintings/heade-painting