Black Salt

http://www.historytoday.com/blog/2012/11/black-salt
http://www.tandfonline.com/doi/abs/10.1080/00253359.2013.785155?journalCode=rmir20#.VDz6ZfldVRo
http://www.liverpooluniversitypress.co.uk/search/hfclient.isa?A=BOOKSONIX_LUP_BOOKSHOP&F=form&AS=FIND%7CIB%7C&AS2=%7CAND%7CU1%7CA/F&view=wrapper&AS1=9781846318184
http://www.ebay.ca/ctg/Black-Salt-Seafarers-African-Descent-British-Ships-Ray-Costello-2012-Hardcover-/144082352
http://www.bookdepository.com/Black-Salt-Ray-Costello/9781781380147
http://www.bol.com/nl/p/black-salt-seafarers-of-african-descent-on-british-ships/9200000034036277/

Of Interest
http://www.writingonthewall.org.uk/wow-news/301-black-family-history-in-the-first-world-war.html