Verity Burgmann, 'Rosa, Samuel Albert (Sam) (1866–1940)', Australian Dictionary of Biography, National Centre of Biography, Australian National University, published first in hardcopy 1988, accessed online 10 July 2017 http://adb.anu.edu.au/biography/rosa-samuel-albert-sam-8264
Email from Jenny Higgins, Register Officer, Australian Dictionary of Biography, 25 August 2017 ("born on 31 January 1866 at Bethnal Green, London, the son of Mary Elizabeth Henshaw, and registered as Henry Thomas Henshaw. He was baptised as Samuel Albert Rosa at Trinity Church, Marylebone on 10 October 1869, after the marriage of his mother to Alexander Rosa, the previous year. ... I suspect from naming patterns etc, that he wasn't the child of Alexander Rosa.")