Honour, H., and Fleming, J. (1999). A World History of Art.
Scott, D. (2017). A Comprehensive Guide to Composition For Artists. https://drawpaintacademy.com/understanding-composition-for-artists/. Visited 12 October 2020.
Scott, D. (2018). Visual Elements - The Building Blocks of Your Painting. https://drawpaintacademy.com/visual-elements/ Visited 3 October 2020.
Tate. (2020). Composition - Art Term. https://www.tate.org.uk/art/art-terms/c/composition. Visited 12 October 2020.

Images:

1 The Venus of Willendorf. Photo by Matthias Kabel, licensed under GNU Free Documentation License.
2 Jean-Honoré Fragonard, 1767. The Swing. Image courtesy of Wikimedia Commons.
3 Hugo Simberg, 1895. Spring Feeling. Image courtesy of Finnish National Gallery.
4 Leonardo da Vinci, 1503. The Virgin and Child with Saint Anne. courtesy of Wikimedia Commons.