"toilets", Encyclopedia of Contemporary Japanese Culture, ed. Sandra Buckley, London/New York: Routledge, 2002, ISBN 9780415143448.
Jennifer Phillips, ed. Suzanne McQuade, "Personal Hygiene", In the Know in Japan: The Indispensable Cross-cultural Guide to Working and Living in Japan, New York: Terra Cognita/Living Language, 2003, ISBN 9780609611142.
Andrew Horvat, Japanese Beyond Words: How to Walk and Talk Like a Native Speaker, Berkeley, California: Stone Bridge, 2000, ISBN 9781880656426, pp. 28-29.
Harvey Luskin Molotch, Where Stuff Comes from: How Toasters, Toilets, Cars, Computers, and Many Other Things Come to Be As They Are, New York: Routledge, 2003, ISBN 9780415944007, pp. 101-02.
Jean-Michel Léger, Derniers domiciles connus: enquête sur les nouveaux logements, 1970-1990, Ministère de l'équipement, du logement, des transports et de l'espace, Paris: Créaphis, 1990, ISBN 9782907150187, p. 129(ในภาษาฝรั่งเศส)
