| Douglas | W. | Boatowner | Albany | 1885 | Herald Almanack |
| Douglas | W. | Machinist | Geraldton | 1885 | Herald Almanack |
| Douglas | W. | Engineer | Victoria District (Geraldton) | 1886 | WA Almanack |
| Douglas | W. | Engineer | Victoria District (Geraldton) | 1886 | WA Almanack |
| Douglas | W. | Engineer | Geraldton | 1887 | WA Almanack |
| Douglas | W. | Engineer | Geraldton | 1888 | WA Almanack |
| Douglas | W. | Labourer | Perth | 1889 | WA Almanack |
| Douglas | W. | Engineer | Geraldton | 1889 | WA Almanack |
| Douglas | W. | Locksmith | Geraldton | 1897 | Witton's Directory |
| Douglas | Wm. | Boatowner | Albany | 1887 | WA Almanack |
| Douglas | Wm. | Boatowner | Albany | 1888 | WA Almanack |
| Douglas | Wm. | Boatowner | Albany | 1889 | WA Almanack |
| Douglas | Wm. | Laborer | Karridale | 1897 | Witton's Directory |
| Douglas & Co | | Sharebrokers & Special Cyclist's Agents | Victoria Buildings, Bayley Street, Coolgardie | 1897 | Witton's Directory |
| Douglas & Co. | - | Drapers and Importers | Fremantle | 1888 | WA Almanack |
| Douglas & Co. | - | Draper | Perth | 1889 | WA Almanack |
| Douglas & Co. | - | Draper and Importers | Fremantle | 1889 | WA Almanack |
| Douglas Bros. | - | Blacksmiths | Perth | 1877 | Herald Almanack |
| Douglas Bros. | - | Blacksmiths | Perth | 1878 | Herald Almanack |
| Douglas Bros. | - | Blacksmiths | Perth | 1880 | Herald Almanack |
| Douglass | A. | Gardener | Perth | 1884 | WA Almanack |
| Douglass | A. | Machinist | Shaw Street, Coolgardie | 1897 | Witton's Directory |
| Douglass | Bros. | Smiths | Perth | 1875 | WA Almanack |
| Douglass | J | Dairyman | Perth | 1875 | WA Almanack |
| Douglass | J. | Dairyman | South Perth, Perth | 1873 | Herald Almanack |
| Douglass | J. | Dairyman | Perth | 1874 | Herald Almanack |
| Douglass | J. | Dairyman | Perth | 1875 | Herald Almanack |
| Douglass | J. | Dairyman | Perth | 1875 | WA Almanack |
| Douglass | J. | Dairyman | Perth | 1876 | Herald Almanack |
| Douglass | J. | Dairyman | Perth | 1876 | WA Almanack |
| Douglass | J. | Dairyman | Perth | 1877 | Herald Almanack |
| Douglass | J. | Dairyman | Perth | 1877 | WA Almanack |
| Douglass | J. | Dairyman | Perth | 1878 | Herald Almanack |
| Douglass | J. | Dairyman | Perth | 1879 | Herald Almanack |
| Douglass | J. | Dairyman | Perth | 1880 | Herald Almanack |
| Douglass | J. | Dairyman | Perth | 1881 | Herald Almanack |
| Douglass | T. | Dairyman | Perth | 1879 | WA Almanack |
| Douglass | T. | Dairyman | Perth | 1880 | WA Almanack |
| Douglass | T. | Dairyman | Perth | 1881 | WA Almanack |
| Douglass | T. | Dairyman | Perth | 1882 | WA Almanack |
| Douglass | T. | Dairyman | Perth | 1884 | WA Almanack |
| Douglass | Thos. | Engineer | Canning | 1880 | WA Almanack |
| Douglass | W. | Storekeeper | Perth | 1876 | WA Almanack |
| Douglass | Wm. | Blacksmith | Victoria District (Geraldton) | 1880 | WA Almanack |
| Douglass | Wm. | Blacksmith | Victoria District (Geraldton) | 1881 | WA Almanack |
| Douglass | Wm. | Blacksmith | Victoria Districts (Geraldton) | 1882 | WA Almanack |
| Douglass & Ashby | - | Gardeners | Perth | 1881 | WA Almanack |
| Douglass And Ashby | - | Gardeners | Perth | 1882 | WA Almanack |
| Douglass Bros. | - | Smiths &c. | Perth | 1876 | WA Almanack |
| Douglass Bros. | - | Smiths &c. | Perth | 1877 | WA Almanack |
