“The Bowker Children”. bowker.info (16 September 2007). 31 December 2008時点のオリジナルよりアーカイブ。10 November 2012閲覧。
doi.org
Cohen, Alan (2000). “Mary Elizabeth Barber: South Africa's first lady natural historian”. Archives of Natural History27 (2): 187–208. doi:10.3366/anh.2000.27.2.187. ISSN0260-9541.
Cohen, Alan (1999). “Mary Elizabeth Barber, the Bowkers and South African Prehistory”. The South African Archaeological Bulletin54 (170): 120. doi:10.2307/3889290. ISSN00381969.
“The Bowker Children”. bowker.info (16 September 2007). 31 December 2008時点のオリジナルよりアーカイブ。10 November 2012閲覧。
worldcat.org
search.worldcat.org
Cohen, Alan (2000). “Mary Elizabeth Barber: South Africa's first lady natural historian”. Archives of Natural History27 (2): 187–208. doi:10.3366/anh.2000.27.2.187. ISSN0260-9541.
Cohen, Alan (1999). “Mary Elizabeth Barber, the Bowkers and South African Prehistory”. The South African Archaeological Bulletin54 (170): 120. doi:10.2307/3889290. ISSN00381969.