| Plummer, William; ISMA Directory; 1908 | ISMA Directory | 1908-00-00 | IOWA | Captain |
| Plummer, William; ISMA Directory; 1909 | ISMA Directory | 1909-00-00 | CITY OF RACINE | Captain |
| Plummer, William; ISMA Directory; 1910 | ISMA Directory | 1910-00-00 | IOWA | Captain |
| Plummer, William; ISMA Directory; 1911 | ISMA Directory | 1911-00-00 | | Captain |
| Plummer, William; ISMA Directory; 1924 | ISMA Directory | 1924-00-00 | | |
| Plummer, William; ISMA Directory; 1925 | ISMA Directory | 1925-00-00 | | |
| Plummer, William; ISMA Directory; 1926 | ISMA Directory | 1926-00-00 | | |
| Plummer, William; ISMA Directory; 1927 | ISMA Directory | 1927-00-00 | | |
| Plummer, William; ISMA Directory; 1928 | ISMA Directory | 1928-00-00 | | |
| Plummer, William; ISMA Directory; 1929 | ISMA Directory | 1929-00-00 | | |
| Plummer, William; ISMA Directory; 1931 | ISMA Directory | 1931-00-00 | | |
| Plummer, William; ISMA Directory; 1932 | ISMA Directory | 1932-00-00 | | |
| Plummer, William; ISMA Directory; 1933 | ISMA Directory | 1933-00-00 | | |