| Hendricus Antonius B. Koopman | Johanna M Van Doesburg |
| b. 11 Apr 1893, Amsterdam (NH) The Netherlands d. 9 Dec 1971, Amsterdam (NH) The Netherlands bur. occ. edu. |
b. 22 Feb 1901, Amsterdam (NH) The Netherlands d. 12 Aug 1986, Amsterdam (NH) The Netherlands bur. occ. edu. |
| J. J. Koopman (Living) |