Charlotte Perkins Gilman (2015). “Women and Economics - A Study of the Economic Relation Between Men and Women as a Factor in Social Evolution: From the famous American writer, feminist, social reformer and a respected sociologist who holds an important place in feminist fiction, well-known for her stories The Yellow Wallpaper and Herland”, p.13, e-artnow
Gretchen Rubin (2009). “The Happiness Project: Or, Why I Spent a Year Trying to Sing in the Morning, Clean My Closets, Fight Right, Read Aristotle, and Generally Have More Fun”, p.8, Harper Collins