^p.456 "The ideas of ethnicity and ethnic group have a long history, often related to "otherness". In the 20th century and beyond, the idea of what constitutes an ethnic group has changed, once associated with minority status and later with cultural characteristics, ethnicity is most recently viewed as the outcome of a social process" Richard T. Schaefer. Encyclopedia of race, ethnicity, and society. SAGE Publications. 2008 [11 December 2012]. ISBN 978-1-4129-2694-2. （原始内容存档于2014-09-22）.