Laughton, Leonard George Carr; Anderson, Roger Charles; Perrin, William Gordon (1 Jan 1974). The Mariner's Mirror (بالإنجليزية). Society for Nautical Research. Archived from the original on 2022-08-06. Retrieved 2016-12-13.
Laughton, Leonard George Carr; Anderson, Roger Charles; Perrin, William Gordon (1 Jan 1974). The Mariner's Mirror (بالإنجليزية). Society for Nautical Research. Archived from the original on 2022-08-06. Retrieved 2016-12-13.