Norris, Anne, and Kathleen Ford. 2000. "Patterns of Union Formation among Urban Minority Youth." Archives of Sexual Behavior, 29(2), 177-188.
Since 1990, several large surveys of sexual behavior have been conducted. In addition to collecting general information on sexual histories, such as number of partners in the previous year and whether subjects ever used condoms, these studies collected information on sexual behavior with specific partners, or "partnerships."