Thomas Hobbes (2015). “Annotated LEVIATHAN with English Grammar Exercises: by Thomas Hobbes (Author), Robert Powell (Editor)”, p.12, Powell Publications, LLC
Charlotte Perkins Gilman (2015). “The Humanness of Women: Theory and Practice of Feminism (Essays and Sketches): Studies and thoughts by the famous American writer, feminist, social reformer and deeply respected sociologist who holds an important place in feminist fiction, known for The Yellow Wallpaper story”, p.86, e-artnow