Swift, Joe (2012). “Summer at the plot”. Joe's Allotment: Planning and planting a productive plot. Random House. ISBN9781409070139. https://books.google.com/books?id=6c3UyYKo1EEC2018年1月20日閲覧. "I suppose it is an atavistic connection with the land and the completely honourable peasant mentality, that was lost in Britain with the Industrial Revolution, yet persists in our gardens and allotments."
Brower, Lincoln P.; Taylor, Orley R.; Williams, Ernest H.; Slayback, Daniel A.; Zubieta, Raul R.; Ramírez, M. Isabel (March 2012). “Decline of monarch butterflies overwintering in Mexico: is the migratory phenomenon at risk?: Decline of monarch butterflies in Mexico”. Insect Conservation and Diversity5 (2): 95–100. doi:10.1111/j.1752-4598.2011.00142.x. hdl:2060/20140010155.
Brower, Lincoln P.; Taylor, Orley R.; Williams, Ernest H.; Slayback, Daniel A.; Zubieta, Raul R.; Ramírez, M. Isabel (March 2012). “Decline of monarch butterflies overwintering in Mexico: is the migratory phenomenon at risk?: Decline of monarch butterflies in Mexico”. Insect Conservation and Diversity5 (2): 95–100. doi:10.1111/j.1752-4598.2011.00142.x. hdl:2060/20140010155.